Preamble Pre.1-Pre.5

 
 
 
 

INTERNATIONAL CODE OF BOTANICAL NOMENCLATURE
 
 

                                         PREAMBLE

 

1.  Botany requires a precise and simple system of nomenclature used by
botanists in all countries, dealing on the one hand with the terms which
denote the ranks of taxonomic groups or units, and on the other hand with
the scientific names which are applied to the individual taxonomic groups
of plants ¹. The purpose of giving a name to a taxonomic group is not to
indicate its characters or history, but to supply a means of referring to it
and to indicate its taxonomic rank. This Code aims at the provision of a
stable method of naming taxonomic groups, avoiding and rejecting the use
of names which may cause error or ambiguity or throw science into con-
fusion. Next in importance is the avoidance of the useless creation of
names. Other considerations, such as absolute grammatical correctness,
regularity or euphony of names, more or less prevailing custom, regard for
persons, etc., notwithstanding their undeniable importance, are relatively
accessory.

2.  The Principles form the basis of the system of botanical nomenclature.

3.  The detailed Provisions are divided into Rules, set out in the Articles,
and Recommendations. Examples (Ex.) are added to the rules and recom-
mendations to illustrate them.

4.  The object of the Rules is to put the nomenclature of the past into order
and to provide for that of the future; names contrary to a rule cannot be
maintained.

5.  The Recommendations deal with subsidiary points, their object being
to bring about greater uniformity and clarity, especially in future nomen-
clature; names contrary to a recommendation cannot, on that account, be
rejected, but they are not examples to be followed.

———————————————————————

¹In this Code, unless otherwise indicated, the word “plant” means any organism tradition-
  ally studied by botanists (see Pre. 7).

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Pre.6-Pre.11 Preamble

6.  The provisions regulating the governance of this Code form its last
division.

7.  The rules and recommendations apply to all organisms traditionally
treated as plants, whether fossil or non-fossil ¹, e.g., blue-green algae (Cy-
anobacteria)
 ² ; fungi, including chytrids, oomycetes, and slime moulds;
photosynthetic protists and taxonomically related non-photosynthetic
groups. Provisions for the names of hybrids appear in App. I.

8.  The International code of nomenclature for cultivated plants is pre-
pared under the authority of the International Commission for the Nomen-
clature of Cultivated Plants and deals with the use and formation of names
for special plant categories in agricultural, forestry, and horticultural no-
menclature.

9.  The only proper reasons for changing a name are either a more pro-
found knowledge of the facts resulting from adequate taxonomic study or
the necessity of giving up a nomenclature that is contrary to the rules.

10.  In the absence of a relevant rule or where the consequences of rules
are doubtful, established custom is followed.

11.  This edition of the Code supersedes all previous editions.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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¹In this Code, the term “fossil” is applied to a taxon when its name is based on a fossil
  type and the term “non-fossil” is applied to a taxon when its name is based on a non-
  fossil type (see Art. 13.3).

²For the nomenclature of other prokaryote groups, see the International code of nomen-
  clature of bacteria.

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Principles I-VI

 
 
 
 

DIVISION I. PRINCIPLES

 
 

Principle I

Botanical nomenclature is independent of zoological and bacteriological
nomenclature. The Code applies equally to names of taxonomic groups
treated as plants whether or not these groups were originally so treated
(see Pre. 7).

Principle II

The application of names of taxonomic groups is determined by means of
nomenclatural types.

Principle III

The nomenclature of a taxonomic group is based upon priority of publica-
tion.

Principle IV

Each taxonomic group with a particular circumscription, position, and
rank can bear only one correct name, the earliest that is in accordance with
the Rules, except in specified cases.

Principle V

Scientific names of taxonomic groups are treated as Latin regardless of
their derivation.

Principle VI

The Rules of nomenclature are retroactive unless expressly limited.

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1-3 Taxa & Ranks

 
 
 
 

DIVISION II. RULES AND RECOMMENDATIONS
 
 

CHAPTER I. TAXA AND THEIR RANKS
 
 

Article 1

1.1.  Taxonomic groups of any rank will, in this Code, be referred to as
taxa (singular: taxon).

1.2.  Fossil taxa may be treated as morphotaxa. A morphotaxon is defined
as a fossil taxon which, for nomenclatural purposes, comprises only the
parts, life-history stages, or preservational states represented by the corre-
sponding nomenclatural type.

1.3.  As in the case of form-taxa for asexual forms (anamorphs) of certain
pleomorphic fungi (Art. 59), the provisions of this Code authorize the
publication and use of names of morphotaxa (Art. 11.7).

Article 2

2.1.  Every individual plant is treated as belonging to an indefinite number
of taxa of consecutively subordinate rank, among which the rank of spec-
cies (species) is basic.

Article 3

3.1.  The principal ranks of taxa in descending sequence are: kingdom
(regnum), division or phylum (divisio, phylum), class (classis), order
(ordo), family (familia), genus (genus), and species (species). Thus, each
species is assignable to a genus, each genus to a family, etc.

3.2.  The principal ranks of nothotaxa (hybrid taxa) are nothogenus and
nothospecies. These ranks are the same as genus and species. The addition
of “notho”
indicates the hybrid character (see App. I).

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Taxa 4-5

Article 4

4.1.  The secondary ranks of taxa in descending sequence are tribe (tribus)
between family and genus, section (sectio) and series (series) between
genus and species, and variety (varietas) and form (forma) below species.

4.2.  If a greater number of ranks of taxa is desired, the terms for these
are made by adding the prefix sub- to the terms denoting the principal or
secondary ranks. A plant may thus be assigned to taxa of the following
ranks (in descending sequence): regnum, subregnum, divisio or phylum,
subdivisio
or subphylum, classis, subclassis, ordo, subordo, familia, sub-
familia, tribus, subtribus, genus, subgenus, sectio, subsectio, series, sub-
series, species, subspecies, varietas, subvarietas, forma, subforma
.

4.3.  Further ranks may also be intercalated or added, provided that confu-
sion or error is not thereby introduced.

4.4.  The subordinate ranks of nothotaxa are the same as the subordinate
ranks of non-hybrid taxa, except that nothogenus is the highest rank per-
mitted (see App. I).

Note 1.  Throughout this Code the phrase “subdivision of a family” refers only to
taxa of a rank between family and genus and “subdivision of a genus” refers only
to taxa of a rank between genus and species.

Note 2.  For the designation of certain categories of plants used in agriculture,
forestry, and horticulture, see Art. 28 Notes 2-5.

Note 3.  In classifying parasites, especially fungi, authors who do not give spe-
cific, subspecific, or varietal value to taxa characterized from a physiological
standpoint but scarcely or not at all from a morphological standpoint may distin-
guish within the species special forms (formae speciales) characterized by their
adaptation to different hosts, but the nomenclature of special forms is not gov-
erned by the provisions of this Code.

Article 5

5.1.  The relative order of the ranks specified in Art. 3 and 4 must not be
altered (see Art. 33.7 and 33.8).

 
 
 
 
 
 

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6 Status definitions

 
 
 
 

CHAPTER II. STATUS, TYPIFICATION, AND PRIORITY OF

NAMES

SECTION 1. STATUS DEFINITIONS

Article 6

6.1.  Effective publication is publication in accordance with Art. 29-31.

6.2.  Valid publication of names is publication in accordance with Art. 32-
45 or H.9 (see also Art. 61).

6.3.  In this Code, unless otherwise indicated, the word “name” means a
name that has been validly published, whether it is legitimate or illegiti-
mate (see Art. 12).

Note 1.  When the same name, based on the same type, has been published inde-
pendently at different times by different authors, then only the earliest of these so-
called “isonyms” has nomenclatural status. The name is always to be cited from
its original place of valid publication, and later “isonyms” may be disregarded.

Ex. 1.  Baker (Summary New Ferns: 9. 1892) and Christensen (Index Filic: 44. 1905)
independently published the name Alsophila kalbreyeri as a substitute for A. podophylla
Baker (1891) non Hook. (1857). As published by Christensen, Alsophila kalbreyeri is a
later “isonym” of A. kalbreyeri Baker, without nomenclatural status (see also Art. 33 Ex.
10).

Ex. 2.  In publishing “Canarium pimela Leenh. nom. nov.”, Leenhouts (in Blumea 9: 406.
1959) reused the illegitimate C. pimela K. D. König (1805), attributing it to himself and
basing it on the same type. He thereby created a later “isonym” without nomenclatural
status.

6.4.  An illegitimate name is one that is designated as such in Art. 18.3,
19.5, or 52-54 (see also Art. 21 Note 1 and Art. 24 Note 2). A name which
according to this Code was illegitimate when published cannot become
legitimate later unless it is conserved or sanctioned.

Ex. 3.  Anisothecium Mitten (1869) when published included the previously designated
type of Dicranella (Müll. Hal.) Schimp. (1856). When Dicranella was conserved with a
different type, Anisothecium did not thereby become legitimate.

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Status definitions – Typification 6-7

Ex. 4.  Skeletonemopsis P. A. Sims (1995) was illegitimate when published because it
included the original type of Skeletonema Grev. (1865). When Skeletonema was conserved
with a different type, Skeletonemopsis nevertheless remained illegitimate and had to be
conserved in order to be available for use.

6.5.  A legitimate name is one that is in accordance with the rules, i.e., that
is not illegitimate as defined in Art. 6.4
.

6.6.  At the rank of family or below, the correct name of a taxon with a
particular circumscription, position, and rank is the legitimate name which
must be adopted for it under the rules (see Art. 11).

Ex. 5.  The generic name Vexillifera Ducke (1922), based on the single species V. micran-
thera,
is legitimate. The same is true of the generic name Dussia Krug & Urb. ex Taub.
(1892), based on the single species D. martinicensis. Both generic names are correct when
the genera are thought to be separate. Harms (in Repert. Spec. Nov. Regni Veg. 19: 291.
1924), however, united Vexillifera and Dussia in a single genus; the latter name is the
correct one for the genus with this particular circumscription. The legitimate name Vexil-
lifera
may therefore be correct or incorrect according to different taxonomic concepts.

6.7.  The name of a taxon below the rank of genus, consisting of the name
of a genus combined with one or two epithets, is termed a combination
(see Art. 21, 23, and 24).

Ex. 6.  Combinations: Mouriri subg. Pericrene, Arytera sect. Mischarytera, Gentiana
lutea, Gentiana tenella
var. occidentalis, Equisetum palustre var. americanum, Equisetum
palustre
f. fluitans.

6.8.  Autonyms are such names as can be established automatically under
Art. 22.3 and 26.3, whether or not they appear in print in the publication
in which they are created (see Art. 32.6).

SECTION 2. TYPIFICATION

Article 7

7.1.  The application of names of taxa of the rank of family or below is
determined by means of nomenclatural types (types of names of taxa).
The application of names of taxa in the higher ranks is also determined by
means of types when the names are ultimately based on generic names
(see Art. 10.7).

7.2.  A nomenclatural type (typus) is that element to which the name of a
taxon is permanently attached, whether as a correct name or as a syn-

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7 Typification

onym. The nomenclatural type is not necessarily the most typical or repre-
sentative element of a taxon.

7.3.  A new name published as an avowed substitute (replacement name,
nomen novum) for an older name is typified by the type of the older name
(see Art. 33.3; but see Art. 33 Note 2).

Ex. 1.  Myrcia lucida McVaugh (1969) was published as a nomen novum for M. laevis
O. Berg (1862), an illegitimate homonym of M. laevis G. Don (1832). The type of M. luci-
da
is therefore the type of M. laevis O. Berg (non G. Don), namely, Spruce 3502.

7.4.  A new name formed from a previously published legitimate name
(stat. nov., comb. nov.) is, in all circumstances, typified by the type of the
basionym, even though it may have been applied erroneously to a taxon
now considered not to include that type (but see Art. 48.1 and 59.6).

Ex. 2.  Pinus mertensiana Bong. was transferred to the genus Tsuga by Carrière, who,
however, as is evident from his description, erroneously applied the new combination T.
mertensiana
to another species of Tsuga, namely T. heterophylla (Raf.) Sarg. The combi-
nation Tsuga mertensiana (Bong.) Carrière must not be applied to T. heterophylla but must
be retained for P. mertensiana when that species is placed in Tsuga; the citation in paren-
theses (under Art. 49) of the name of the original author, Bongard, indicates the type of the
name.

Ex. 3.  Delesseria gmelinii J. V. Lamour. (1813), an illegitimate replacement name for
Fucus palmetta S. G. Gmel. (1768), and all intended combinations based on D. gmelinii
(and not excluding the type of F. palmetta; see Art. 48.1) have the same type as F. pal-
metta,
even though the material in Lamouroux’s hands is now assigned to a different spe-
cies, Delesseria bonnemaisonii C. Agardh (1822).

7.5.  A name which, under Art. 52, was illegitimate when published is
either automatically typified by the type of the name which ought to have
been adopted under the rules, or by a different type designated or defi-
nitely indicated by the author of the illegitimate name. Automatic typifi-
cation does not apply to names sanctioned under Art. 15.

7.6.  The type of an autonym is the same as that of the name from which it
is derived.

7.7.  A name validly published by reference to a previously and effec-
tively published description or diagnosis (Art. 32.1(c)) is to be typified by
an element selected from the context of the validating description or diag-
nosis, unless the validating author has definitely designated a different
type (but see Art. 10.2). However, the type of a name of a taxon assigned
to a group with a nomenclatural starting-point later than 1753 (see Art.
13.1) is to be determined in accordance with the indication or descriptive
and other matter accompanying its valid publication (see Art. 32-45).

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Typification 7

Ex. 4.  Since the name Adenanthera bicolor Moon (1824) is validated solely by reference
to Rumphius (Herb. Amboin. 3: t. 112. 1743), the type of the name, in the absence of the
specimen from which it was figured, is the illustration referred to. It is not the specimen, at
Kew, collected by Moon and labelled “Adenanthera bicolor”, since Moon did not defi-
nitely designate the latter as the type.

Ex. 5.  Echium lycopsis L. (Fl. Angl.: 12. 1754) was published without a description or
diagnosis but with reference to Ray (Syn. Meth. Stirp. Brit., ed. 3: 227. 1724), in which a
“Lycopsis” species was discussed with no description or diagnosis but with citation of
earlier references, including Bauhin (Pinax: 255. 1623). The accepted validating descrip-
tion of E. lycopsis is that of Bauhin, and the type must be chosen from the context of his
work. Consequently the Sherard specimen in the Morison herbarium (OXF), selected by
Klotz (in Wiss. Z. Martin-Luther-Univ. Halle-Wittenberg Math.-Naturwiss. Reihe 9: 375-
376. 1960), although probably consulted by Ray, is not eligible as type. The first accept-
able choice is that of the illustration, cited by both Ray and Bauhin, of “Echii altera spe-
cies”
in Dodonaeus (Stirp. Hist. Pempt.: 620. 1583), suggested by Gibbs (in Lagascalia 1:
60-61. 1971) and formally made by Stearn (in Ray Soc. Publ. 148, Introd.: 65. 1973).

7.8.  Typification of names adopted in one of the works specified in Art.
13.1(d), and thereby sanctioned (Art. 15), may be effected in the light of
anything associated with the name in that work.

7.9.  The typification of names of morphogenera of plant fossils (Art. 1.2),
of fungal anamorphs (Art. 59), and of any other analogous genera or lower
taxa does not differ from that indicated above.

Note 1.  See also Art. 59 for details regarding typification of names in certain
pleomorphic fungi.

7.10.  For purposes of priority (Art. 9.17 and 10.5), designation of a type
is achieved only by effective publication (Art. 29-31).

7.11.  For purposes of priority (Art. 9.17 and 10.5), designation of a type
is achieved only if the type is definitely accepted as such by the typifying
author, if the type element is clearly indicated by direct citation including
the term “type” (typus) or an equivalent, and, on or after 1 January 2001,
if the typification statement includes the phrase “here designated” (hic
designatus) or an equivalent.

Ex. 6.  Chlorosarcina Gerneck (1907) originally comprised two species, C. minor and C.
elegans
. Vischer (1933) transferred the former to Chlorosphaera G. A. Klebs and retained
the latter in Chlorosarcina. He did not, however, use the term “type” or an equivalent, so
that his action does not constitute typification of Chlorosarcina. The first to designate a
type, as “LT.”, was Starr (in ING Card No. 16528, Nov 1962), who selected Chlorosar-
cina elegans
.

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7-8 Typification

*Ex. 7.  The phrase “standard species” as used by Hitchcock & Green (in Anon., Nomencl.
Prop. Brit. Botanists: 110-199. 1929) is now treated as equivalent to “type”, and hence
type designations in this work are acceptable.

Recommendation 7A

7A.1.  It is strongly recommended that the material on which the name of a taxon
is based, especially the holotype, be deposited in a public herbarium or other
public collection with a policy of giving bona fide botanists open access to de-
posited material, and that it be scrupulously conserved.

Article 8

8.1.  The type (holotype, lectotype, or neotype) of a name of a species or
infraspecific taxon is either a single specimen conserved in one herbarium
or other collection or institution, or an illustration.

8.2.  For the purpose of typification a specimen is a gathering, or part of a
gathering, of a single species or infraspecific taxon made at one time, dis-

regarding admixtures (see Art. 9.12). It may consist of a single plant, parts
of one or several plants, or of multiple small plants. A specimen is usually
mounted
on a single herbarium sheet or in an equivalent preparation, such
as a
box, packet, jar or microscope slide.

Ex. 1.  “Echinocereus sanpedroensis” (Raudonat & Rischer in Echinocereenfreund
8(4): 91-92. 1995) was based on a “holotype” consisting of a complete plant with
roots, a detached branch, an entire flower, a flower cut in halves, and two fruits,
which according to the label were taken from the same cultivated individual at differ-
ent times and preserved, in alcohol, in a single jar. This material belongs to more than
one gathering and cannot be accepted as a type. Raudonat & Rischer’s name is not
validly published under Art. 37.2.

8.3.  A specimen may be mounted as more than one preparation, as long
as the parts are clearly labelled as being part of that same specimen. Mul-
tiple preparations from a single gathering which are not clearly labelled as
being part of a single specimen are duplicates ¹, irrespective of whether
the source was one plant or more than one (but see Art. 8.5).

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* Here and elsewhere in the Code, a prefixed asterisk denotes a “voted Example”, accepted
   by a Congress in order to legislate nomenclatural practice when the corresponding Article
   of the Code is open to divergent interpretration or does not adequately cover the matter.

¹  Here and elsewhere in this Code, the word duplicate is given its usual meaning in her-
   barium curatorial practice. It is part of a single gathering of a single species or in-
   fraspecific taxon made by the same collector(s) at one time. The possibility of a mixed
   gathering must always be considered by an author choosing a lectotype, and corre-
   sponding caution used.

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Typification 8-8A

Ex. 2.  The holotype specimen of Delissea eleeleensis H. St. John, Christensen 261
(BISH), is mounted as two preparations, a herbarium sheet (BISH No. 519675) bear-
ing the annotation “fl. bottled” and an inflorescence preserved in alcohol in a jar la-
belled “Cyanea, Christensen 261”. The annotation indicates that the inflorescence is
part of the holotype specimen and not a duplicate, nor is it part of the isotype speci-
men (BISH No. 519676), which is not labelled as including additional material pre-
served in a separate preparation.

Ex. 3.  The holotype specimen of Johannesteijsmannia magnifica J. Dransf., Drans-
field 862
(K), consists of a leaf mounted on five herbarium sheets, an inflorescence
and infructescence in a box, and liquid-preserved material in a bottle.

Ex. 4.  The holotype of Cephaëlis acanthacea Steyerm., Cuatrecasas 16752 (F), con-
sists of a single specimen mounted on two herbarium sheets, labelled “sheet 1” and
“sheet 2”. Although the two sheets have separate herbarium numbers, F-1153741 and
F-1153742, respectively, the cross-labelling indicates that they constitute a single
specimen. A third sheet of Cuatrecasas 16572, F-1153740, is not cross-labelled and is
therefore a duplicate.

Ex. 5.  The holotype specimen of Eugenia ceibensis Standl., Yuncker & al. 8309, is
mounted on a single herbarium sheet at F. A fragment was removed from the speci-
men subsequent to its designation as holotype and is now conserved in LL. The frag-
ment is mounted on a herbarium sheet along with a photograph of the holotype and is
labelled “fragment of type!”. The fragment is no longer part of the holotype specimen
because it is not permanently conserved in the same herbarium as the holotype. Such
fragments have the status of a duplicate, i.e. an isotype.

8.4.  Type specimens of names of taxa must be preserved permanently and
may not be living plants or cultures. However, cultures of fungi and algae,
if preserved in a metabolically inactive state (e.g. by lyophilization or
deep-freezing), are acceptable as types.

Ex. 6.  The strain CBS 7351 is acceptable as the type of the name Candida populi Hagler
& al. (in Int. J. Syst. Bacteriol. 39: 98. 1989) because it is permanently preserved in a
metabolically inactive state by lyophilization (see also Rec. 8B.2).

8.5.  The type, epitypes (Art. 9.7) excepted, of the name of a taxon of
fossil plants of the rank of species or below is always a specimen (see Art.
9.13). One whole specimen is to be considered as the nomenclatural type
(see Rec. 8A.3).

Recommendation 8A

8A.1.  When a holotype, a lectotype, or a neotype is an illustration, the specimen
or specimens upon which that illustration is based should be used to help deter-
mine the application of the name (see also Art. 9.13).

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8A-9 Typification

8A.2.  When an illustration is designated as the type of a name under Art. 37.4,
the collection data of the illustrated material should be given (see also Rec.
32D.2).

8A.3.  If the type specimen of a name of a fossil plant is cut into pieces (sections
of fossil wood, pieces of coalball plants, etc.), all parts originally used in estab-
lishing the diagnosis ought to be clearly marked.

8A.4.  When a single specimen designated as type is mounted as multiple prepa-
rations, this should be stated in the protologue ¹, and the preparations appropri-
ately labelled.

Recommendation 8B

8B.1.  Whenever practicable a living culture should be prepared from the holo-
type material of the name of a newly described taxon of fungi or algae and de-
posited in at least two institutional culture or genetic resource collections. (Such
action does not obviate the requirement for a holotype specimen under Art. 8.4.)

8B.2.  In cases where the type of a name is a culture permanently preserved in a
metabolically inactive state (see Art. 8 Ex. 6), any living isolates obtained from
that should be referred to as “ex-type” (ex typo), “ex-holotype” (ex holotypo),
“ex-isotype” (ex isotypo), etc., in order to make it clear they are derived from the
type but are not themselves the nomenclatural type.

Article 9

9.1.  A holotype of a name of a species or infraspecific taxon is the one
specimen or illustration (but see Art. 37.4) used by the author, or desig-
nated by the author as the nomenclatural type. As long as a holotype is
extant, it fixes the application of the name concerned (but see Art. 9.13;
see also Art. 10).

Note 1.  Any designation made by the original author, if definitely expressed at
the time of the original publication of the name of the taxon, is final (but see Art.
9.9 and 9.13). If the author used only one element, that one must be accepted as
the holotype. If a new name is based on a previously published description or
diagnosis of the taxon, the same considerations apply to material included by the
earlier author (see Art. 7.7 and 7.8).

9.2.  A lectotype is a specimen or illustration designated from the original
material as the nomenclatural type, in conformity with Art. 9.9 and 9.10,

———————————————————————

¹Protologue (from the Greek protos, first; logos, discourse): everything associated with a
  name at its valid publication, i.e. description or diagnosis, illustrations, references, syn-
  onymy, geographical data, citation of specimens, discussion, and comments.

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if no holotype was indicated at the time of publication, or if it is missing,
or if it
is found to belong to more than one taxon (see also Art. 9.13).

Note 2.  For the purposes of this Code, the original material comprises: (a) those
specimens and illustrations (both unpublished and published either prior to or
together with the protologue) upon which it can be shown that the description or
diagnosis validating the name was based; (b) the holotype and those specimens
which, even if not seen by the author of the description or diagnosis validating the
name, were indicated as types (syntypes or paratypes) of the name at its valid
publication; and (c) the isotypes or isosyntypes of the name irrespective of
whether such specimens were seen by either the author of the validating descrip-
tion or diagnosis, or the author of the name.

9.3.  An isotype is any duplicate of the holotype; it is always a specimen.

9.4.  A syntype is any specimen cited in the protologue when no holotype
was designated, or any one of two or more specimens simultaneously des-
ignated as types.

9.5.  A paratype is a specimen cited in the protologue that is neither the
holotype nor an isotype, nor one of the syntypes if two or more specimens
were simultaneously designated as types.

Ex. 1.   The holotype of the name Rheedia kappleri Eyma, which applies to a polygamous
species, is a male specimen collected by Kappler (593a in U). The author designated a
hermaphroditic specimen collected by the Forestry Service of Surinam as a paratype
(B. W. 1618 in U).

Note 3.  In most cases in which no holotype was designated there will also be no
paratypes, since all the cited specimens will be syntypes. However, when an
author designated two or more specimens as types (Art. 9.4), any remaining cited
specimens are paratypes and not syntypes.

9.6.  A neotype is a specimen or illustration selected to serve as nomen-
clatural type as long as all of the material on which the name of the taxon
was based is missing (see also Art. 9.15).

9.7.  An epitype is a specimen or illustration selected to serve as an inter-
pretative type when the holotype, lectotype, or previously designated
neotype, or all original material associated with a validly published name,
is demonstrably ambiguous and cannot be critically identified for pur-
poses of the precise application of the name of a taxon. When an epitype
is designated, the holotype, lectotype, or neotype that the epitype supports
must be explicitly cited (see Art. 9.18).

Ex. 2.   The holotype of Vitellaria paradoxa C. F. Gaertn. (1807) is a seed of unknown
provenance (P), clearly belonging to the species currently known as Butyrospermum para-
doxum
(C. F. Gaertn.) Hepper. However, the two subspecies recognized within that species

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can only be distinguished by characters of foliage or inflorescence. Hall & Hurdle (in
Taxon 44: 410. 1995) designated an epitype with foliage, Mungo Park (BM). It belongs to
the western subspecies, now to be known as B. paradoxum subsp. paradoxum.

9.8.  The use of a term defined in the Code (Art. 9.1-9.7) as denoting
a type, in a sense other than that in which it is so defined, is treated as an
error to be corrected (for example, the use of the term lectotype to denote
what is in fact a neotype).

Ex. 3.   Borssum Waalkes (in Blumea 14: 198. 1966) cited Herb. Linnaeus No. 866.7
(LINN) as the holotype of Sida retusa L. (1763). The term is incorrectly used because
illustrations in Plukenet (Phytographia: t. 9, f. 2. 1691) and Rumphius (Herb. Amboin. 6:
t. 19. 1750) were cited by Linnaeus in the protologue of S. retusa. Since all three elements
are original material (Art. 9 Note 2), Borssum Waalkes’s use of holotype is an error to be
corrected to lectotype.

Ex. 4.   In describing the Jurassic dinoflagellate species Nannoceratopsis triceras, Drugg
(1978) designated a holotype (slide preparation) and one isotype (SEM preparation) from
the same locality, age, and zone. He also cited two other specimens which are from a
different locality, stage, and zone as “isotypes”. Drugg’s second use of the term isotype is
an error and is to be corrected to “paratype”.

9.9.  If no holotype was indicated by the author of a name of a species or
infraspecific taxon, or when the holotype has been lost or destroyed, or
when the material designated as type is found to belong to more than one
taxon, a lectotype or, if permissible (Art. 9.6), a neotype as a substitute for
it may be designated (Art. 7.10 and 7.11).

9.10.  In lectotype designation, an isotype must be chosen if such exists,
or otherwise a syntype if such exists. If no isotype, syntype or isosyntype
(duplicate of syntyp
e) is extant, the lectotype must be chosen from among
the paratypes if such exist. If no cited specimens exist, the lectotype must
be chosen from among the uncited specimens and cited and uncited illus-
trations which comprise the remaining original material, if such exist.

9.11.  If no original material is extant, a neotype may be selected. A lec-
totype always takes precedence over a neotype, except as provided by Art.
9.15.  

9.12.  When a type specimen (herbarium sheet or equivalent preparation)
contains parts belonging to more than one taxon (see Art. 9.9), the name
must remain attached to that part which corresponds most nearly with the
original description or diagnosis.

Ex. 5.   The type of the name Tillandsia bryoides Griseb. ex Baker (1878) is Lorentz 128
(BM)
; this specimen, however, proved to be mixed. Smith (in Proc. Amer. Acad. Arts 70:
192. 1935) acted in accordance with Art. 9.12 in designating one part of Lorentz’s speci-
men
as the lectotype.

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9.13.  The holotype (or lectotype) of a name of a species or infraspecific
taxon of fossil plants (Art. 8.5) is the specimen (or one of the specimens)
on which the validating illustrations (Art. 38) are based. When, prior to
1 January 2001 (see Art. 38.2), in the protologue of a name of a new taxon
of fossil plants of the rank of species or below, a type specimen is indi-
cated (Art. 37.1) but not identified among the validating illustrations, a
lectotype must be designated from among the specimens illustrated in the
protologue. This choice is superseded if it can be demonstrated that the
original type specimen corresponds to another validating illustration.

9.14.  A designation of a lectotype or neotype that later is found to refer to
a single gathering but more than one specimen must nevertheless be ac-
cepted (subject to Art. 9.17), but may be further narrowed to a single one
of these specimens by way of a subsequent lectotypification or neotypifi-
cation.

Ex. 6.   Erigeron plantagineus Greene (1898) was described from material collected by R.
M. Austin in California. Cronquist (in Brittonia 6: 173. 1947) wrote “Type: Austin s.n.,
Modoc County, California (ND)”, thereby designating the Austin material in ND as the
[first-step] lectotype. Strother & Ferlatte (in Madroño 35: 85. 1988), noting that there were
two specimens of this gathering at ND, designated one of them (ND-G No. 057228) as the
[second-step] lectotype. In subsequent references, both lectotypification steps may be cited
in sequence.

9.15.  When a holotype or a previously designated lectotype has been lost
or destroyed and it can be shown that all the other original material differs
taxonomically from the destroyed type, a neotype may be selected to pre-
serve the usage established by the previous typification (see also Art.
9.16).

9.16.  A neotype selected under Art. 9.15 may be superseded if it can be
shown to differ taxonomically from the holotype or lectotype that it re-
placed.

9.17.  The author who first designates a lectotype or a neotype must be
followed, but that choice is superseded if (a) the holotype or, in the case
of a neotype, any of the original material is rediscovered; the choice may
also be superseded if one can show that (b) it is in serious conflict with the
protologue and another element is available that is not in conflict with the
protologue, or that (c) it is contrary to Art. 9.12.

9.18.  The author who first designates an epitype must be followed; a dif-
ferent epitype may be designated only if the original epitype is lost or de-
stroyed. A lectotype or neotype supported by an epitype may be superseded
in accordance with Art. 9.17 or, in the case of a neotype, Art. 9.16. If it
can be shown that an epitype and the type it supports differ taxonomically

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9-9A Typification

and that neither Art. 9.16 nor 9.17 applies, the name may be proposed for
conservation with a conserved type (Art. 14.9; see also Art. 57).

Note 4.  An epitype supports only the type to which it is linked by the typifying
author. If the supported type is superseded, the epitype has no standing with re-
spect to the replacement type.

9.19.  Designation of an epitype is not effected unless the herbarium or
institution in which the epitype is conserved is specified or, if the epitype
is a published illustration, a full and direct bibliographic reference to it is
provided.

9.20.  On or after 1 January 1990, lectotypification or neotypification of a
name of a species or infraspecific taxon by a specimen or unpublished
illustration is not effected unless the herbarium or institution in which the
type is conserved is specified.

9.21.  On or after 1 January 2001, lectotypification or neotypification of a
name of a species or infraspecific taxon is not effected unless indicated
by use of the term “lectotypus” or “neotypus”, its abbreviation, or its
equivalent in a modern language (but see Art. 9.8).

Recommendation 9A

9A.1.  Typification of names for which no holotype was designated should only
be carried out with an understanding of the author’s method of working; in par-
ticular it should be realized that some of the material used by the author in de-
scribing the taxon may not be in the author’s own herbarium or may not even
have survived, and conversely, that not all the material surviving in the author’s
herbarium was necessarily used in describing the taxon.

9A.2.  Designation of a lectotype should be undertaken only in the light of an
understanding of the group concerned. In choosing a lectotype, all aspects of the
protologue should be considered as a basic guide. Mechanical methods, such as
the automatic selection of the first element cited or of a specimen collected by the
person after whom a species is named, should be avoided as unscientific and
productive of possible future confusion and further changes.

9A.3.  In choosing a lectotype, any indication of intent by the author of a name
should be given preference unless such indication is contrary to the protologue.
Such indications are manuscript notes, annotations on herbarium sheets, recog-
nizable figures, and epithets such as typicus, genuinus, etc.

9A.4.  When a single collection is cited in the protologue, but a particular institu-
tion housing this is not designated, it should be assumed that the specimen housed
in the institution where the author is known to have worked is the holotype, un-
less there is evidence that further material of the same collection was used.

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9A.5.  When two or more heterogeneous elements were included in or cited with
the original description or diagnosis, the lectotype should be so selected as to
preserve current usage. In particular, if another author has already segregated one
or more elements as other taxa, the residue or part of it should be designated as
the lectotype provided that this element is not in conflict with the original de-
scription or diagnosis (see Art. 9.17).

Recommendation 9B

9B.1.  In selecting a neotype, particular care and critical knowledge should be
exercised because the reviewer usually has no guide except personal judgement
as to what best fits the protologue; if this selection proves to be faulty it will in-
evitably result in further change.

Article 10

10.1.  The type of a name of a genus or of any subdivision of a genus is
the type of a name of a species (except as provided by Art. 10.4). For pur-
poses of designation or citation of a type, the species name alone suffices,
i.e., it is considered as the full equivalent of its type.

Note 1.  Terms such as “holotype”, “syntype”, and “lectotype”, as presently de-
fined in Art. 9, although not applicable, strictly speaking, to the types of names in
ranks higher than species, are so used by analogy.

10.2.  If in the protologue of the name of a genus or of any subdivision of
a genus the holotype or lectotype of one or more previously or simultane-
ously published species name(s) is definitely included (see Art. 10.3), the
type must be chosen (Art. 7.10 and 7.11) from among these types unless
the type was indicated (Art. 22.6, 22.7, 37.1 and 37.3) or designated by
the author of the name. If no type of a previously or simultaneously pub-
lished species name was definitely included, a type must be otherwise
chosen, but the choice is to be superseded if it can be demonstrated that
the selected type is not conspecific with any of the material associated
with the protologue.

Ex. 1.  The genus Anacyclus, as originally circumscribed by Linnaeus (1753), comprised
three validly named species. Cassini (in Cuvier, Dict. Sci. Nat. 34: 104. 1825) designated
Anthemis valentina L. (1753) as type of Anacyclus, but this was not an original element of
the genus. Green (in Anon., Nomencl. Prop. Brit. Botanists: 182. 1929) designated Anacy-
clus valentinus
L. (1753), “the only one of the three original species still retained in the
genus”, as the “standard species” (see Art. 7 Ex. 7), and her choice must be followed (Art.
10.5). Humphries (in Bull. Brit. Mus. (Nat. Hist.) Bot. 7: 109. 1979) designated a specimen
in the Clifford Herbarium (BM) as lectotype of Anacyclus valentinus, and that specimen
thereby became the ultimate type of the generic name.

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10 Typification

Ex. 2.  Castanella Spruce ex Benth. & Hook. f. (1862) was described on the basis of a
single specimen and without mention of a species name. Swart (in ING Card No. 2143.
1957) was the first to designate a type (as “T.”): C. granatensis Triana & Planch. (1862),
based on a Linden collection. As long as the Spruce specimen is considered to be con-
specific with Linden’s collection Swart’s type designation cannot be superseded, even
though the Spruce specimen became the type of Paullinia paullinioides Radlk. (1896), be-
cause the latter is not a “previously or simultaneously published species name”.

10.3.  For the purposes of Art. 10.2, definite inclusion of the type of a
name of a species is effected by citation of, or reference (direct or indi-
rect) to, a validly published name, whether accepted or synonymized by
the author, or by citation of the holotype or lectotype of a previously or
simultaneously published name of a species.

Ex. 3.  The protologue of Elodes Adans. (1763) included references to “Elodes” of Clusius
(1601), “Hypericum” of Tournefort (1700), and Hypericum aegypticum L. (1753). The
latter is the only reference to a validly published name of a species, and neither of the other
elements is the type of a name of a species. The type of H. aegypticum is therefore the type
of Elodes, even though subsequent authors designated H. elodes L. (1759) as the type (see
Robson in Bull. Brit. Mus. (Nat. Hist.), Bot. 5: 305, 336. 1977).

10.4.  By and only by conservation (Art. 14.9), the type of a name of a
genus may be a specimen or illustration, preferably used by the author in
the preparation of the protologue, other than the type of a name of an in-
cluded species.

Ex. 4.  Physconia Poelt (1965) was originally conserved with the specimen “‘Lichen pul-
verulentus’,
Germania, Lipsia in Tilia, 1767, Schreber (M)” as the type. That specimen is
the type of P. pulverulacea Moberg (1979), which name is now cited in the type entry in

App. IIIA.

Note 2.  If the element designated under Art. 10.4 is the type of a species name,
that name may be cited as the type of the generic name. If the element is not the
type of a species name, a parenthetical reference to the correct name of the type
element may be added.

Ex. 5.  Pseudolarix Gordon (1858) was conserved with a specimen from the Gordon her-
barium as its conserved type. As this specimen is not the type of any species name, its
accepted identity “[= P. amabilis (J. Nelson) Rehder ... ]” has been added to the corre-
sponding entry in App. IIIA.

10.5.  The author who first designates a type of a name of a genus or sub-
division of a genus must be followed, but the choice may be superseded if
(a) it can be shown that it is in serious conflict with the protologue and an-
other element is available which is not in conflict with the protologue, or
(b) that it was based on a largely mechanical method of selection.

Ex. 6.  Fink (in Contr. U.S. Natl. Herb. 14(1): 2. 1910) specified that he was “stating the
types of the genera according to the ‘first species’ rule”. His type designations may there-
fore be superseded. For example, Fink had designated Biatorina griffithii (Ach.) A. Mas-

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Typification – Priority 10-11

sal. as the type of Biatorina A. Massal.; but his choice was superseded when the next
subsequent designation, by Santesson (in Symb. Bot. Upsal. 12(1): 428. 1952), stated a
different type, B. atropurpurea (Schaerer) A. Massal.

*Ex. 7.  Authors following the American code of botanical nomenclature, Canon 15 (in
Bull. Torrey Bot. Club 34: 172. 1907), designated as the type “the first binomial species in
order” eligible under certain provisions. This method of selection is to be considered as
largely mechanical. Thus the first type designation for Delphinium L., by Britton (in Brit-
ton & Brown, Ill. Fl. N. U.S., ed. 2, 2: 93. 1913), who followed the American code and
chose D. consolida L., has been superseded under Art. 10.5(b) by the designation of
D. peregrinum L. by Green (in Anon., Nomencl. Prop. Brit. Botanists: 162. 1929). The
unicarpellate D. consolida could not have been superseded as type by the tricarpellate
D. peregrinum under Art. 10.5(a), however, because it is not in serious conflict with the
generic protologue, which specifies “germina tria vel unum”, the assignment of the genus
to “Polyandria Trigynia” by Linnaeus notwithstanding.

10.6.  The type of a name of a family or of any subdivision of a family is
the same as that of the generic name on which it is based (see Art. 18.1).
For purposes of designation or citation of a type, the generic name alone
suffices. The type of a name of a family or subfamily not based on a ge-
neric name is the same as that of the corresponding alternative name (Art.
18.5 and 19.7).

10.7.  The principle of typification does not apply to names of taxa above
the rank of family, except for names that are automatically typified by
being based on generic names (see Art. 16). The type of such a name is
the same as that of the generic name on which it is based.

Note 3.  For the typification of some names of subdivisions of genera see Art.
22.6 and 22.7.

Recommendation 10A

10A.1.  When a combination in a rank of subdivision of a genus has been pub-
lished under a generic name that has not yet been typified, the type of the generic
name should be selected from the subdivision of the genus that was designated as
nomenclaturally typical, if that is apparent.

SECTION 3. PRIORITY

Article 11

11.1.  Each family or taxon of lower rank with a particular circumscrip-
tion, position, and rank can bear only one correct name, special exceptions
being made for 9 families and 1 subfamily for which alternative names are
permitted (see Art. 18.5 and 19.7). However, the use of separate names for

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the form-taxa of fungi and for morphotaxa of fossil plants is allowed un-
der Art. 1.3 and 59.4-59.5.

11.2.  In no case does a name have priority outside the rank in which it is
published (but see Art. 53.4).

Ex. 1.  Campanula sect. Campanopsis R. Br. (Prodr.: 561. 1810) when treated as a genus
is called Wahlenbergia Roth (1821), a name conserved against the taxonomic (heterotypic)
synonym Cervicina Delile (1813), and not Campanopsis (R. Br.) Kuntze (1891).

Ex. 2.  Magnolia virginiana var. foetida L. (1753) when raised to specific rank is called
M. grandiflora L. (1759), not M. foetida (L.) Sarg. (1889).

Ex. 3.  Lythrum intermedium Ledeb. (1822) when treated as a variety of L. salicaria L.
(1753) is called L. salicaria var. glabrum Ledeb. (Fl. Ross. 2: 127. 1843), not L. salicaria
var. intermedium (Ledeb.) Koehne (in Bot. Jahrb. Syst. 1: 327. 1881).

Ex. 4.  When the two varieties constituting Hemerocallis lilioasphodelus L. (1753), var. flava
L. and var. fulva L., are considered to be distinct species, the one not including the lectotype
of the species name is called H. fulva (L.) L. (1762), but the other one bears the name H.
lilioasphodelus
L., which in the rank of species has priority over H. flava (L.) L. (1762).

11.3.  For any taxon from family to genus inclusive, the correct name is
the earliest legitimate one with the same rank, except in cases of limitation
of priority by conservation (see Art. 14) or where Art. 11.7, 15, 19.4, 56,
57, or 59 apply.

Ex. 5.  When Aesculus L. (1753), Pavia Mill. (1754), Macrothyrsus Spach (1834) and
Calothyrsus Spach (1834) are referred to a single genus, its name is Aesculus L.

11.4.  For any taxon below the rank of genus, the correct name is the com-
bination of the final epithet¹ of the earliest legitimate name of the taxon in
the same rank, with the correct name of the genus or species to which it is
assigned, except (a) in cases of limitation of priority under Art. 14, 15, 56,
or 57, or (b) if the resulting combination would be invalid under Art.
32.1(b) or illegitimate under Art. 53, or (c) if Art. 11.7, 22.1, 26.1, or 59
rule that a different combination is to be used.

Ex. 6.  Primula sect. Dionysiopsis Pax (in Jahresber. Schles. Ges. Vaterländ. Kultur 87: 20.
1909) when transferred to Dionysia Fenzl becomes D. sect. Dionysiopsis (Pax) Melch. (in
Mitt. Thüring. Bot. Vereins 50: 164-168. 1943); the substitute name D. sect. Ariadna
Wendelbo (in Bot. Not. 112: 496. 1959) is illegitimate.

Ex. 7.  Antirrhinum spurium L. (1753) when transferred to Linaria Mill. is called L. spuria
(L.) Mill. (1768).

Ex. 8.  When transferring Serratula chamaepeuce L. (1753) to Ptilostemon Cass., Cassini
illegitimately named the species P. muticus Cass. (1826). In that genus, the correct name is
P. chamaepeuce (L.) Less. (1832).

———————————————————————

¹ Here and elsewhere in this Code, the phrase “final epithet” refers to the last epithet in
  sequence in any particular combination, whether in the rank of a subdivision of a genus,
  or of a species, or of an infraspecific taxon.

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Ex. 9.  Spartium biflorum Desf. (1798) when transferred to Cytisus Desf. could not be
called C. biflorus because of the previously and validly published C. biflorus L’Hér.
(1791); the substitute name C. fontanesii Spach (1849) was therefore correctly proposed.

Ex. 10.  Spergula stricta Sw. (1799) when transferred to Arenaria L. is called A. uliginosa
Schleich. ex Schltdl. (1808) because of the existence of the name A. stricta Michx. (1803),
based on a different type; but on further transfer to the genus Minuartia L. the epithet
stricta is again available and the species is called M. stricta (Sw.) Hiern (1899).

Ex. 11.  Arum dracunculus L. (1753) when transferred to Dracunculus Mill. is named
D. vulgaris Schott (1832), as use of the Linnaean epithet would result in a tautonym.

Ex. 12.  Cucubalus behen L. (1753) when transferred to Behen Moench was legitimately
renamed B. vulgaris Moench (1794) to avoid the tautonym “B. behen”. In Silene L., the
epithet behen is unavailable because of the existence of S. behen L. (1753). Therefore, the
substitute name S. cucubalus Wibel (1799) was proposed. This, however, is illegitimate
since the specific epithet vulgaris was available. In Silene, the correct name of the species
is S. vulgaris (Moench) Garcke (1869).

Ex. 13.  Helianthemum italicum var. micranthum Gren. & Godr. (Fl. France 1: 171. 1847)
when transferred as a variety to H. penicillatum Thibaud ex Dunal retains its varietal epi-
thet and is named H. penicillatum var. micranthum (Gren. & Godr.) Grosser (in Engler,
Pflanzenr. 14: 115. 1903).

Note 1.  The valid publication of a name at a rank lower than genus precludes any
simultaneous homonymous combination (Art. 53), irrespective of the priority of
other names with the same final epithet that may require transfer to the same
genus or species.

Ex. 14.  Tausch included two species in his new genus Alkanna: A. tinctoria Tausch
(1824), a new species based on “Anchusa tinctoria” in the sense of Linnaeus (1762), and
A. plukenetii Tausch 1824, a nomen novum based on Lithospermum tinctorium L. (1753).
Both names are legitimate and take priority from (1824).

Ex. 15.  Raymond-Hamet transferred to the genus Sedum both Cotyledon sedoides DC.
(1808) and Sempervivum sedoides Decne. (1844). He combined the epithet of the later
name, Sempervivum sedoides, under Sedum as S. sedoides (Decne.) Hamet (1929), and
published a new name, S. candollei Hamet (1929), for the earlier name. Both names are
legitimate.

11.5.  When, for any taxon of the rank of family or below, a choice is
possible between legitimate names of equal priority in the corresponding
rank, or between available final epithets of names of equal priority in the
corresponding rank, the first such choice to be effectively published (Art.
29-31) establishes the priority of the chosen name, and of any legitimate
combination with the same type and final epithet at that rank, over the
other competing name(s) (but see Art. 11.6).

Note 2.  A choice as provided for in Art. 11.5 is effected by adopting one of the
competing names, or its final epithet in the required combination, and simultane-
ously rejecting or relegating to synonymy the other(s), or nomenclatural (homo-
typic) synonyms thereof.

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11 Priority

Ex. 16.  When Dentaria L. (1753) and Cardamine L. (1753) are united, the resulting genus
is called Cardamine because that name was chosen by Crantz (Cl. Crucif. Emend.: 126.
1769), who first united them.

Ex. 17.  When Entoloma (Fr. ex Rabenh.) P. Kumm. (1871), Leptonia (Fr. : Fr.) P. Kumm.
(1871), Eccilia (Fr. : Fr.) P. Kumm. (1871), Nolanea (Fr. : Fr.) P. Kumm. (1871), and
Claudopus Gillet (1876) are united, one of the generic names simultaneously published by
Kummer must be used for the combined genus. Donk, who did so (in Bull. Jard. Bot.
Buitenzorg, ser. 3, 18(1): 157. 1949), selected Entoloma, which is therefore treated as
having priority over the other names.

Ex. 18.  Brown (in Tuckey, Narr. Exped. Zaire: 484. 1818) was the first to unite Waltheria
americana
L. (1753) and W. indica L. (1753). He adopted the name W. indica for the com-
bined species, and this name is accordingly treated as having priority over W. americana.

Ex. 19.  Baillon (in Adansonia 3: 162. 1863), when uniting for the first time Sclerocroton
integerrimus
Hochst. (1845) and S. reticulatus Hochst. (1845), adopted the name Stillingia
integerrima
(Hochst.) Baill. for the combined taxon. Consequently Sclerocroton integer-
rimus
is treated as having priority over S. reticulatus irrespective of the genus (Sclerocro-
ton, Stillingia, Excoecaria, Sapium)
to which the species is assigned.

Ex. 20.  Linnaeus (1753) simultaneously published the names Verbesina alba and V. pro-
strata
. Later (1771), he published Eclipta erecta, an illegitimate name because V. alba was
cited in synonymy, and E. prostrata, based on V. prostrata. The first author to unite these
taxa was Roxburgh (Fl. Ind. 3: 438. 1832), who adopted the name E. prostrata (L.) L.
Therefore V. prostrata is treated as having priority over V. alba.

Ex. 21.  Donia speciosa and D. formosa, which were simultaneously published by Don
(1832), were illegitimately renamed Clianthus oxleyi and C. dampieri by Lindley (1835).
Brown (1849) united both in a single species, adopting the illegitimate name C. dampieri
and citing D. speciosa and C. oxleyi as synonyms; his choice is not of the kind provided
for by Art. 11.5. C. speciosus (D. Don) Asch. & Graebn. (1909), published with D. spe-
ciosa
and C. dampieri listed as synonyms, is an illegitimate later homonym of C. speciosus
(Endl.) Steud. (1840); again, conditions for a choice under Art. 11.5 were not satisfied.
Ford & Vickery (1950) published the legitimate combination C. formosus (D. Don) Ford &
Vickery and cited D. formosa and D. speciosa as synonyms, but since the epithet of the
latter was unavailable in Clianthus a choice was not possible and again Art. 11.5 does not
apply. Thompson (1990) was the first to effect an acceptable choice when publishing the
combination Swainsona formosa (D. Don) Joy Thomps. and indicating that D. speciosa
was a synonym of it.

11.6.  An autonym is treated as having priority over the name or names of
the same date and rank that established it.

Note 3.  When the final epithet of an autonym is used in a new combination under
the requirements of Art. 11.6, the basionym of that combination is the name from
which the autonym is derived, or its basionym if it has one.

Ex. 22.  Heracleum sibiricum L. (1753) includes H. sibiricum subsp. lecokii (Godr. &
Gren.) Nyman (Consp. Fl. Europ.: 290. 1879) and H. sibiricum subsp. sibiricum automati-
cally established at the same time. When H. sibiricum is included in H. sphondylium L.
(1753) as a subspecies, the correct name for the taxon is H. sphondylium subsp. sibiricum

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Priority 11

(L.) Simonk. (Enum. Fl. Transsilv.: 266. 1887), not subsp. lecokii, whether or not subsp.
lecokii is treated as distinct.

Ex. 23.  The publication of Salix tristis var. microphylla Andersson (Salices Bor.-Amer.:
21. 1858) created the autonym S. tristis Aiton (1789) var. tristis, dating from 1858. If
S. tristis, including var. microphylla, is recognized as a variety of S. humilis Marshall
(1785), the correct name is S. humilis var. tristis (Aiton) Griggs (in Proc. Ohio Acad. Sci.
4: 301. 1905). However, if both varieties of S. tristis are recognized as varieties of S. hu-
milis,
then the names S. humilis var. tristis and S. humilis var. microphylla (Andersson)
Fernald (in Rhodora 48: 46. 1946) are both used.

Ex. 24.  In the classification adopted by Rollins and Shaw, Lesquerella lasiocarpa (Hook.
ex A. Gray) S. Watson (1888) is composed of two subspecies, subsp. lasiocarpa (which
includes the type of the name of the species and is cited without an author) and subsp. ber-
landieri
(A. Gray) Rollins & E. A. Shaw. The latter subspecies is composed of two varie-
ties. In that classification the correct name of the variety which includes the type of subsp.
berlandieri is L. lasiocarpa var. berlandieri (A. Gray) Payson (1922), not L. lasiocarpa
var. berlandieri (cited without an author) or L. lasiocarpa var. hispida (S. Watson) Rollins
& E. A. Shaw (1972), based on Synthlipsis berlandieri var. hispida S. Watson (1882),
since publication of the latter name established the autonym S. berlandieri A. Gray var.
berlandieri which, at varietal rank, is treated as having priority over var. hispida.

11.7.  For purposes of priority, names of fossil taxa (diatoms excepted)
compete only with names based on a fossil type representing the same
part, life-history stage, or preservational state (see Art. 1.2).

Ex. 25.  The generic name Sigillaria Brongn. (1822), established for bark fragments, may
in part represent the same biological taxon as the “cone-genus” Mazocarpon M. J. Benson
(1918), which represents permineralizations, or Sigillariostrobus (Schimp.) Geinitz (1873),
which represents compressions. Certain species of all three genera, Sigillaria, Mazocar-
pon,
and Sigillariostrobus, have been assigned to the family Sigillariaceae. All these
generic names can be used concurrently in spite of the fact that they may, at least in part,
apply to the same organism.

Ex. 26.  The morphogeneric name Tuberculodinium D. Wall (1967) may be retained for a
genus of fossil cysts even though cysts of the same kind are known to be part of the life
cycle of an extant genus that bears an earlier name, Pyrophacus F. Stein (1883).

Note 4.  Names of plants (diatoms excepted) based on a non-fossil type are
treated as having priority over names of the same rank based on a fossil (or sub-
fossil) type.

Ex. 27.  If Platycarya Siebold & Zucc. (1843), a non-fossil genus, and Petrophiloides
Bowerb. (1840), a fossil genus, are united, the name Platycarya is accepted for the com-
bined genus, although it is antedated by Petrophiloides.

Ex. 28.  Boalch and Guy-Ohlson (in Taxon 41: 529-531. 1992) united the two prasinophyte
genera Pachysphaera Ostenf. (1899) and Tasmanites E. J. Newton (1875). Pachysphaera
is based on a non-fossil type and Tasmanites on a fossil type. Under the Code in effect in
1992, Tasmanites had priority and was therefore adopted. Under the current Code, in
which the exemption in Art. 11.7 applies only to diatoms and not to algae in general,
Pachysphaera is correct for the combined genus.

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11-13 Priority-Starting points

Ex. 29.  The generic name Metasequoia Miki (1941) was based on the fossil type of M.
disticha
(Heer) Miki. After discovery of the non-fossil species M. glyptostroboides Hu
& W. C. Cheng, conservation of Metasequoia Hu & W. C. Cheng (1948) as based on the
non-fossil type was approved. Otherwise, any new generic name based on M. glyptostro-
boides
would have had to be treated as having priority over Metasequoia Miki.

11.8.  For purposes of priority, names in Latin form given to hybrids are
subject to the same rules as are those of non-hybrid taxa of equivalent
rank.

Ex. 30.  The name ×Solidaster H. R. Wehrh. (1932) antedates ×Asterago Everett (1937) for
the hybrids between Aster L. and Solidago L.

Ex. 31.  Anemone ×hybrida Paxton (1848) antedates A. ×elegans Decne. (1852), pro sp., as
the binomial for the hybrids derived from A. hupehensis (Lemoine & E. Lemoine) Le-
moine & E. Lemoine × A. vitifolia Buch.-Ham. ex DC.

Ex. 32.  Camus (in Bull. Mus. Natl. Hist. Nat. 33: 538. 1927) published the name
×Agroelymus A. Camus for a nothogenus, without a Latin description or diagnosis, men-
tioning only the names of the parents involved (Agropyron Gaertn. and Elymus L.). Since
this name was not validly published under the Code then in force, Rousseau (in Mém. Jard.
Bot. Montréal 29: 10-11. 1952) published a Latin diagnosis. However, the date of valid
publication of ×Agroelymus under this Code (Art. H.9) is 1927, not 1952, so it antedates
the name ×Elymopyrum Cugnac (in Bull. Soc. Hist. Nat. Ardennes 33: 14. 1938).

11.9.  The principle of priority is not mandatory for names of taxa above
the rank of family (but see Rec. 16B).

Article 12

12.1.  A name of a taxon has no status under this Code unless it is validly
published (see Art. 32-45).

SECTION 4. LIMITATION OF THE PRINCIPLE OF PRIORITY

Article 13

13.1.  Valid publication of names for plants of the different groups is
treated as beginning at the following dates (for each group a work is men-
tioned which is treated as having been published on the date given for that
group):

Non-fossil plants:

(a)   Spermatophyta and Pteridophyta, 1 May 1753 (Linnaeus, Spe-
       cies plantarum, ed. 1).

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Starting points 13

(b)   Musci (the Sphagnaceae excepted), 1 January 1801 (Hedwig, Species
       muscorum).

(c)   Sphagnaceae and Hepaticae, 1 May 1753 (Linnaeus, Species plan-
       tarum, ed. 1).

(d)   Fungi (including slime moulds and lichen-forming fungi), 1 May
       1753 (Linnaeus, Species plantarum, ed. 1). Names in the Uredinales,
       Ustilaginales, and Gasteromycetes (s. l.) adopted by Persoon (Synopsis
       methodica fungorum, 31 December 1801) and names of other fungi
       (excluding slime moulds) adopted by Fries (Systema mycologicum,
       vol. 1 (1 January 1821) to 3, with additional Index (1832), and Elen-
       chus fungorum, vol. 1-2), are sanctioned (see Art. 15). For nomencla-
       tural purposes names given to lichens shall be considered as applying
       to their fungal component.

(e)   Algae, 1 May 1753 (Linnaeus, Species plantarum, ed. 1). Exceptions:

       Nostocaceae homocysteae, 1 January 1892 (Gomont, “Monogra-
       phie des Oscillariées”, in Ann. Sci. Nat., Bot., ser. 7, 15: 263-368; 16:
       91-264). The two parts of Gomont’s “Monographie”, which appeared
       in 1892 and 1893, respectively, are treated as having been published
       simultaneously on 1 January 1892.

       Nostocaceae heterocysteae, 1 January 1886 (Bornet & Flahault,
       “Révision des Nostocacées hétérocystées”, in Ann. Sci. Nat., Bot., ser.
       7, 3: 323-381; 4: 343-373; 5: 51-129; 7: 177-262). The four parts of
       the “Révision”, which appeared in 1886, 1886, 1887, and 1888, re-
       spectively, are treated as having been published simultaneously on
       1 January 1886.

       Desmidiaceae (s. l.), 1 January 1848 (Ralfs, British Desmidieae).

       Oedogoniaceae, 1 January 1900 (Hirn, “Monographie und Icono-
       graphie der Oedogoniaceen”, in Acta Soc. Sci. Fenn. 27(1)).

Fossil plants:

(f)   All groups, 31 December 1820 (Sternberg, Flora der Vorwelt, Ver-
       such 1: 1-24, t. 1-13). Schlotheim’s Petrefactenkunde (1820) is re-
       garded as published before 31 December 1820.

13.2.  The group to which a name is assigned for the purposes of this Arti-
cle is determined by the accepted taxonomic position of the type of the
name.

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13-14 Starting points-Conservation

Ex. 1.  The genus Porella and its single species, P. pinnata, were referred by Linnaeus
(1753) to the Musci; since the type specimen of P. pinnata is now accepted as belonging to
the Hepaticae, the names were validly published in 1753.

Ex. 2.  The designated type of Lycopodium L. (1753) is L. clavatum L. (1753) and the type
specimen of this is currently accepted as a pteridophyte. Accordingly, although the genus
is listed by Linnaeus among the Musci, the generic name and the names of the pterido-
phyte species included by Linnaeus under it were validly published in 1753.

13.3.  For nomenclatural purposes, a name is treated as pertaining to a
non-fossil taxon unless its type is fossil in origin. Fossil material is distin-
guished from non-fossil material by stratigraphic relations at the site of
original occurrence. In cases of doubtful stratigraphic relations, provisions
for non-fossil taxa apply.

13.4.  Generic names which appear in Linnaeus’s Species plantarum, ed. 1
(1753) and ed. 2 (1762-1763), are associated with the first subsequent de-
scription given under those names in Linnaeus’s Genera plantarum, ed. 5
(1754) and ed. 6 (1764). The spelling of the generic names included in
Species plantarum, ed. 1, is not to be altered because a different spelling
has been used in Genera plantarum, ed. 5.

13.5.  The two volumes of Linnaeus’s Species plantarum, ed. 1 (1753),
which appeared in May and August, 1753, respectively, are treated as
having been published simultaneously on 1 May 1753.

Ex. 3.  The generic names Thea L. (Sp. Pl.: 515. 24 Mai 1753), and Camellia L. (Sp. Pl.:
698. 16 Aug 1753; Gen. Pl., ed. 5: 311. 1754), are treated as having been published simul-
taneously on 1 May 1753. Under Art. 11.5 the combined genus bears the name Camellia,
since Sweet (Hort. Suburb. Lond.: 157. 1818), who was the first to unite the two genera,
chose that name, and cited Thea as a synonym.

13.6.  Names of anamorphs of fungi with a pleomorphic life cycle do not,
irrespective of priority, affect the nomenclatural status of the names of the
correlated holomorphs (see Art. 59.4).

Article 14

14.1.  In order to avoid disadvantageous nomenclatural changes entailed
by the strict application of the rules, and especially of the principle of
priority in starting from the dates given in Art. 13, this Code provides, in
App. II and III, lists of names of families, genera, and species that are
conserved (nomina conservanda). Conserved names are legitimate even
though initially they may have been illegitimate.

14.2.  Conservation aims at retention of those names which best serve
stability of nomenclature (see Rec. 50E).

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Conservation 14

14.3.  The application of both conserved and rejected names is determined
by nomenclatural types. The type of the specific name cited as the type of
a conserved generic name may, if desirable, be conserved and listed in
App. IIIA.

14.4.  A conserved name of a family or genus is conserved against all
other names in the same rank based on the same type (nomenclatural, i.e.
homotypic, synonyms, which are to be rejected) whether or not these are
cited in the corresponding list as rejected names, and against those names
based on different types (taxonomic, i.e. heterotypic, synonyms) that are
listed as rejected ¹. A conserved name of a species is conserved against all
names listed as rejected, and against all combinations based on the re-
jected names.

Note 1.  The Code does not provide for conservation of a name against itself, i.e.
against the same name with the same type but with a different place and date of
valid publication than is given in the relevant entry in App. II or III, and perhaps
with a different authorship (but see Art. 14.9).

Note 2.  A species name listed as conserved or rejected in App. IIIB may have
been published as the name of a new taxon, or as a combination based on an ear-
lier name. Rejection of a name based on an earlier name does not in itself pre-
clude the use of the earlier name since that name is not “a combination based on a
rejected name” (Art. 14.4).

Ex. 1.  Rejection of Lycopersicon lycopersicum (L.) H. Karst. in favour of L. esculentum
Mill. does not preclude the use of the homotypic Solanum lycopersicum L.

14.5.  When a conserved name competes with one or more names based
on different types and against which it is not explicitly conserved, the
earliest of the competing names is adopted in accordance with Art. 11, ex-
cept for some conserved family names (App. IIB), which are conserved
against unlisted names.

Ex. 2.  If Weihea Spreng. (1825) is united with Cassipourea Aubl. (1775), the combined
genus will bear the prior name Cassipourea, although Weihea is conserved and Cas-
sipourea
is not.

Ex. 3.  If Mahonia Nutt. (1818) is united with Berberis L. (1753), the combined genus will
bear the prior name Berberis, although Mahonia is conserved and Berberis is not.

Ex. 4.  Nasturtium R. Br. (1812) was conserved only against the homonym Nasturtium
Mill. (1754) and the nomenclatural (homotypic) synonym Cardaminum Moench (1794);
consequently if reunited with Rorippa Scop. (1760) it must bear the name Rorippa.

———————————————————————

¹The International code of zoological nomenclature and the International code of nomen-
  clature of bacteria use the terms “objective synonym” and “subjective synonym” for no-
  menclatural and taxonomic synonym, respectively.

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14 Conservation

14.6.  When a name of a taxon has been conserved against an earlier name
based on a different type, the latter is to be restored, subject to Art. 11, if it
is considered the name of a taxon at the same rank distinct from that of the
nomen conservandum, except when the earlier rejected name is a homo-
nym of the conserved name.

Ex. 5.  The generic name Luzuriaga Ruiz & Pav. (1802) is conserved against the earlier
names Enargea Banks ex Gaertn. (1788) and Callixene Comm. ex Juss. (1789). If, how-
ever, Enargea is considered to be a separate genus, the name Enargea is retained for it.

14.7.  A rejected name, or a combination based on a rejected name, may
not be restored for a taxon which includes the type of the corresponding
conserved name.

Ex. 6.  Enallagma Baill. (1888) is conserved against Dendrosicus Raf. (1838), but not
against Amphitecna Miers (1868); if Enallagma and Amphitecna are united, the combined
genus must bear the name Amphitecna, although the latter is not explicitly conserved
against Dendrosicus.

14.8.  The listed type of a conserved name may not be changed except by
the procedure outlined in Art. 14.12.

Ex. 7.  Bullock & Killick (in Taxon 6: 239. 1957) published a proposal that the listed type
of Plectranthus L’Hér. be changed from P. punctatus (L. f.) L’Hér. to P. fruticosus L’Hér.
This proposal was approved by the appropriate Committees and by an International Bo-
tanical Congress.

14.9.  A name may be conserved with a different type from that desig-
nated by the author or determined by application of the Code (see also
Art. 10.4). Such a name may be conserved either from its place of valid
publication (even though the type may not then have been included in the
named taxon) or from a later publication by an author who did include the
type as conserved. In the latter case the original name and the name as
conserved are treated as if they were homonyms (Art. 53), whether or not
the name as conserved was accompanied by a description or diagnosis of
the taxon named.

Ex. 8.  Bromus sterilis L. (1753) has been conserved from its place of valid publication
even though its conserved type, a specimen (Hubbard 9045, E) collected in 1932, was not
originally included in Linnaeus’s species.

Ex. 9.  Protea L. (1753) did not include the conserved type of the generic name, P. cyna-
roides
(L.) L. (1771), which in 1753 was placed in the genus Leucadendron. Protea was
therefore conserved from the 1771 publication, and Protea L. (1771), although not de-
signed to be a new generic name and still including the original type elements, is treated as
if it were a validly published homonym of Protea L. (1753).

14.10.  A conserved name, with any corresponding autonym, is conserved
against all earlier homonyms. An earlier homonym of a conserved name is

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Conservation 14-14A

not made illegitimate by that conservation but is unavailable for use; if not
otherwise illegitimate
, it may serve as basionym of another name or com-
bination based on the same type (see also Art. 55.3).

Ex. 10.  The generic name Smithia Aiton (1789), conserved against Damapana Adans.
(1763), is thereby conserved automatically against the earlier homonym Smithia Scop.
(1777).

14.11.  A name may be conserved in order to preserve a particular spelling
or gender. A name so conserved is to be attributed without change of pri-
ority to the author who validly published it, not to an author who later
introduced the conserved spelling or gender.

Ex. 11.  The spelling Rhodymenia, used by Montagne (1839), has been conserved against
the original spelling Rhodomenia, used by Greville (1830). The name is to be cited as
Rhodymenia Grev. (1830).

Note 3.  The date of conservation does not affect the priority (Art. 11) of a con-
served name, which is determined only on the basis of the date of valid publica-
tion (Art. 32-45).

14.12.  The lists of conserved names will remain permanently open for
additions and changes. Any proposal of an additional name must be ac-
companied by a detailed statement of the cases both for and against its
conservation. Such proposals must be submitted to the General Committee
(see Div. III), which will refer them for examination to the committees for
the various taxonomic groups.

14.13.  Entries of conserved names may not be deleted.

14.14.  When a proposal for the conservation of a name, or of its rejection
under Art.
56, has been approved by the General Committee after study by
the Committee for the taxonomic group concerned, retention (or rejection)
of that name is authorized subject to the decision of a later International
Botanical Congress.

Recommendation 14A

14A.1.  When a proposal for the conservation of a name, or of its rejection under
Art.
56, has been referred to the appropriate Committee for study, authors should
follow existing usage as far as possible pending the General Committee’s rec-
ommendation on the proposal.

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15 Sanctioning

Article 15

15.1.  Names sanctioned under Art. 13.1(d) are treated as if conserved
against earlier homonyms and competing synonyms. Such names, once
sanctioned, remain sanctioned even if elsewhere in the sanctioning works
the sanctioning author does not recognize them.

Ex. 1.  Agaricus ericetorum Fr. was accepted by Fries in Systema mycologicum (1821), but
later (1828) regarded by him as a synonym of A. umbelliferus L. and not included in his
Index (1832) as an accepted name. Nevertheless A. ericetorum is a sanctioned name.

15.2.  An earlier homonym of a sanctioned name is not made illegitimate
by that sanctioning but is unavailable for use; if not otherwise illegitimate,
it may serve as a basionym of another name or combination based on the
same type (see also Art. 55.3).

Ex. 2.  Patellaria Hoffm. (1789) is an earlier homonym of the sanctioned generic name
Patellaria Fr. (1822) : Fr.. Hoffmann’s name is legitimate but unavailable for use. Lecanidion
Endl. (1830), based on the same type as Patellaria Fr. : Fr., is illegitimate under Art. 52.1.

Ex. 3.  Agaricus cervinus Schaeff. (1774) is an earlier homonym of the sanctioned A.
cervinus
Hoffm. (1789) : Fr.; Schaeffer’s name is unavailable for use, but it is legitimate
and
may serve as basionym for combinations in other genera. In Pluteus Fr. the combina-
tion is cited as P. cervinus (Schaeff.) P. Kumm. and has priority over the taxonomic (hete-
rotypic) synonym P. atricapillus (Batsch) Fayod, based on A. atricapillus Batsch (1786).

15.3.  When, for a taxon from family to and including genus, two or more
sanctioned names compete, Art. 11.3 governs the choice of the correct
name (see also Art. 15.5).

15.4.  When, for a taxon below the rank of genus, two or more sanctioned
names and/or two or more names with the same final epithet and type as a
sanctioned name compete, Art. 11.4 governs the choice of the correct name.

Note 1.  The date of sanctioning does not affect the priority (Art. 11) of a sanc-
tioned name, which is determined only on the basis of valid publication. In par-
ticular, when two or more homonyms are sanctioned only the earliest of them
may be used, the later being illegitimate under Art. 53.2.

Ex. 4.  Fries (Syst. Mycol. 1: 41. 1821) accepted Agaricus flavovirens Pers. (1801), treat-
ing A. equestris L. (1753) as a synonym. Later (Elench. Fung. 1: 6. 1828) he stated “No-
men prius et aptius arte restituendum” and accepted A. equestris. Both names are sanct-
ioned, but when they are considered synonyms A. equestris, having priority, is to be used.

15.5.  A name which neither is sanctioned nor has the same type and final
epithet as a sanctioned name in the same rank may not be applied to a taxon
which includes the type of a sanctioned name in that rank the final epithet
of which is available for the required combination (see Art. 11.4(b)).

15.6.  Conservation (Art. 14) and explicit rejection (Art. 56.1) override
sanctioning.

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Higher taxa 16

 
 
 
 

CHAPTER III. NOMENCLATURE OF TAXA ACCORDING TO

THEIR RANK

SECTION 1. NAMES OF TAXA ABOVE THE RANK OF FAMILY

Article 16

16.1.  The name of a taxon above the rank of family is treated as a noun in
the plural and is written with an initial capital letter. Such names may be
either (a) automatically typified names, formed by replacing the termina-
tion -aceae
in a legitimate name of an included family based on a generic
name
by the termination denoting their rank (preceded by the connecting
vowel -o- if the termination begins with a consonant), as specified in Rec.
16A.1-3 and Art.
17.1; or (b) descriptive names, not so formed, which
apply to taxa with a recognized circumscription and which may be used
unchanged at different ranks.

Ex. 1.  Automatically typified names above the rank of family: Magnoliophyta, based on
Magnoliaceae; Gnetophytina, based on Gnetaceae; Pinopsida, based on Pinaceae; Marat-
tiidae, based on Marattiaceae; Caryophyllidae and Caryophyllales, based on Caryophyl-
laceae; Fucales, based on Fucaceae; Bromeliineae, based on Bromeliaceae.

Ex. 2.  Descriptive names above the rank of family: Anthophyta, Chlorophyta, Parietales;
Ascomycota, Ascomycotina, Ascomycetes; Angiospermae, Centrospermae, Coniferae, Enan-
tioblastae
, Gymnospermae
.

16.2.  For automatically typified names, the name of the subdivision or
subphylum that includes the type of the adopted name of a division or
phylum, the name of the subclass that includes the type of the adopted
name of a class, and the name of the suborder that includes the type of the
adopted name of an order are to be based on the same type as the corre-
sponding higher-ranked name.

Ex. 3.  Pteridophyta Bergen & B. M. Davis (1906) and Pteridophytina B. Boivin (1956);
Gnetopsida Engl. (1898) and Gnetidae Cronquist & al. (1966); Liliales Perleb (1826) and
Liliineae Rchb. (1841).

16.3.  When an automatically typified name above the rank of family has
been published with an improper Latin termination, not agreeing with

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16-16A Higher taxa

those provided for in Rec.16A.1-3 and Art. 17.1, the termination must be
changed to conform with these standards, without change of the author
citation or date of publication (see Art. 32.5). However, if such names are
published with a non-Latin termination they are not validly published.

Ex. 4.  “Cactarieae” (Dumortier, 1829, based on Cactaceae) and “Coriales” (Lindley,
1833, based on Coriariaceae), both published for taxa of the rank of order, are to be cor-
rected to Cactales Dumort. (1829) and Coriariales Lindl. (1833), respectively.

Ex. 5.  However, Acoroidées (Kirschleger, Fl. Alsace 2: 103. 1853 - Jul 1857), published
for a taxon of the rank of order, is not to be accepted as “Acorales Kirschl.”, as it has a
French rather than a Latin termination. The name Acorales was later validly published by
Reveal (in Phytologia 79: 72. 1996).

Note 1.  The terms “divisio” and “phylum”, and their equivalents in modern lan-
guages, are treated as referring to one and the same rank. When “divisio” and
“phylum” are used simultaneously to denote different ranks, this usage is contrary
to Art. 5, and the corresponding names are not validly published (Art. 33.7).

16.4.  Where one of the word elements -monad-, -cocc-, -nemat-, or -clad-,
being the genitive singular stem of the second part of a name of an in-
cluded
genus, has been omitted before the termination -phyceae or -phyta,
the shortened class name or division or phylum name is regarded as based
on the generic name in question if such derivation is obvious or is indi-
cated at establishment of the group name.

Ex. 6.  The name Raphidophyceae Chadef. ex P. C. Silva (1980) was indicated by its
author to be based on Raphidomonas F. Stein (1878).

Note 2.  The principle of priority is not mandatory for names of taxa above the
rank of family (Art. 11.9); but see Rec. 16B).

Recommendation 16A

16A.1.  A name of a division or phylum should end in -phyta unless the taxon is a
division or phylum of fungi, in which case its name should end in -mycota.

16A.2.  A name of a subdivision or subphylum should end in -phytina, unless it is
a subdivision or subphylum of fungi, in which case it should end in -mycotina.

16A.3.  A name of a class or of a subclass should end as follows:

(a)  In the algae: -phyceae (class) and -phycidae (subclass);

(b)  In the fungi: -mycetes (class) and -mycetidae (subclass);

(c)  In other groups of plants: -opsida (class) and -idae, but not -viridae
       (subclass).

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Higher taxa – Families 16B-18

Recommendation 16B

16B.1.  In choosing among typified names for a taxon above the rank of family,
authors should generally follow the principle of priority.

Article 17

17.1.  Automatically typified names of orders or suborders are to end in
-ales (but not -virales) and -ineae, respectively.

17.2.  Names intended as names of orders, but published with their rank
denoted by a term such as “cohors”, “nixus”, “alliance”, or “Reihe” in-
stead of “order”, are treated as having been published as names of orders.

Recommendation 17A

17A.1.  Authors should not publish new names for orders that include a family
from the name of which an existing ordinal name is derived.

SECTION 2. NAMES OF FAMILIES AND SUBFAMILIES, TRIBES AND

SUBTRIBES

Article 18

18.1.  The name of a family is a plural adjective used as a noun; it is
formed from the genitive singular of a legitimate name of an included
genus by replacing the genitive singular inflection (Latin -ae, -i, -us, -is;
transliterated Greek -ou, -os, -es, -as, or -ous, including the latter’s
equivalent -eos) with the termination -aceae (but see Art.18.5). For ge-
neric names of non-classical origin, when analogy with classical names is
insufficient to determine the genitive singular, -aceae is added to the full
word. For generic names with alternative genitives the one implicitly used
by the original author must be maintained.

Ex. 1.  Family names based on a generic name of classical origin: Rosaceae (from Rosa,
Rosae
), Salicaceae (from Salix, Salicis), Plumbaginaceae (from Plumbago, Plumbaginis),
Rhodophyllaceae (from Rhodophyllus, Rhodophylli), Rhodophyllidaceae (from Rhodo-
phyllis, Rhodophyllidos
), Sclerodermataceae (from Scleroderma, Sclerodermatos), Aex-
toxicaceae
(from Aextoxicon, Aextoxicou), Potamogetonaceae (from Potamogeton, Pota-
mogetonos
).

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18 Families

Ex. 2.  Family names based on a generic name of non-classical origin: Nelumbonaceae
(from Nelumbo, Nelumbonis, declined by analogy with umbo, umbonis), Ginkgoaceae
(from Ginkgo, indeclinable).

18.2.  Names intended as names of families, but published with their rank
denoted by one of the terms “order” (ordo) or “natural order” (ordo natu-
ralis
) instead of “family”, are treated as having been published as names
of families (see also Art. 19.2).

Ex. 3.  Cyperaceae Juss. (1789), Lobeliaceae Juss. (1813), and Xylomataceae Fr. (1820)
were published as “ordo Cyperoideae, “ordo naturalis Lobeliaceae”, and “ordo Xylo-
maceae
, respectively.

18.3.  A name of a family based on an illegitimate generic name is ille-
gitimate unless conserved. Contrary to Art. 32.1(b) such a name is validly
published if it complies with the other requirements for valid publication.

Ex. 4.  Caryophyllaceae Juss., nom. cons. (from Caryophyllus Mill. non L.); Winteraceae
R. Br. ex Lindl., nom. cons. (from Wintera Murray, an illegitimate synonym of Drimys J.
R. Forst. & G. Forst.).

18.4.  When a name of a family has been published with an improper
Latin termination, the termination must be changed to conform with the
rule, without change of the author citation or date of publication (see Art.
32.5). However, if such a name is published with a non-Latin termination,
it is not validly published.

Ex. 5.  “Coscinodisceae” (Kützing 1844), published to designate a family, is to be accepted
as Coscinodiscaceae Kütz. 1844 and not attributed to De Toni, who first used the correct
spelling (in Notarisia 5: 915. 1890).

Ex. 6.  “Atherospermeae” (Brown 1814), published to designate a family, is to be accepted
as Atherospermataceae R. Br. and not attributed to Airy Shaw (in Willis, Dict. Fl. Pl.,
ed. 7: 104. 1966), who first used the correct spelling, or to Lindley (Veg. Kingd.: 300.
1846), who used the spelling “Atherospermaceae”.

Ex. 7.  However, Tricholomées (Roze in Bull. Soc. Bot. France 23: 49. 1876), published to
designate a family,
is not to be accepted as “Tricholomataceae Roze”, as it has a French
rather than a Latin termination. The name Tricholomataceae was later validated by Pouzar
(1983; see App. IIA).

18.5.  The following names, of long usage, are treated as validly pub-
lished: Palmae (Arecaceae; type, Areca L.); Gramineae (Poaceae; type,
Poa L.); Cruciferae (Brassicaceae; type, Brassica L.); Leguminosae (Fa-
baceae;
type, Faba Mill. [= Vicia L.]); Guttiferae (Clusiaceae; type, Clu-
sia
L.); Umbelliferae (Apiaceae; type, Apium L.); Labiatae (Lamiaceae;
type, Lamium L.); Compositae (Asteraceae; type, Aster L.). When the Pa-
pilionaceae
(Fabaceae; type, Faba Mill.) are regarded as a family distinct

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Families – Subdivisions of families 18-19

from the remainder of the Leguminosae, the name Papilionaceae is con-
served against Leguminosae.

18.6.  The use, as alternatives, of the family names indicated in parenthe-
ses in Art. 18.5 is authorized.

Article 19

19.1.  The name of a subfamily is a plural adjective used as a noun; it is
formed in the same manner as the name of a family (Art. 18.1) but by
using the termination -oideae instead of -aceae.

19.2.  Names intended as names of subfamilies, but published with their
rank denoted by the term “suborder” (subordo) instead of subfamily, are
treated as having been published as names of subfamilies (see also Art.
18.2).

19.3.  A tribe is designated in a similar manner, with the termination -eae,
and a subtribe similarly with the termination -inae (but not -virinae).

19.4.  The name of any subdivision of a family that includes the type of
the adopted, legitimate name of the family to which it is assigned is to be
based on the generic name equivalent to that type (but see Art. 19.7).

Ex. 1.  The type of the family name Rosaceae Adans. is Rosa L. and hence the subfamily
and tribe which include Rosa are to be called Rosoideae Endl. and Roseae DC.

Ex. 2.  The type of the family name Poaceae Barnhart (nom. alt., Gramineae Adans. – see
Art. 18.5) is Poa L. and hence the subfamily and tribe which include Poa are to be called
Pooideae Asch. and Poëae R. Br.

Note 1.  This provision applies only to the names of those subordinate taxa that
include the type of the adopted name of the family (but see Rec. 19A.2).

Ex. 3.  The subfamily including the type of the family name Ericaceae Juss. (Erica L.),
irrespective of priority, is to be called Ericoideae Endl., and the tribe including this type is
called Ericeae D. Don. However, the correct name of the tribe including both Rhododen-
dron
L., the type of the subfamily name Rhododendroideae Endl., and Rhodora L. is Rho-
doreae
D. Don (1834) not Rhododendreae Brongn. (1843).

Ex. 4.  The subfamily of the family Asteraceae Martinov (nom. alt., Compositae Adans.)
including Aster L., the type of the family name, is irrespective of priority to be called
Asteroideae Asch., and the tribe and subtribe including Aster are to be called Astereae
Cass. and Asterinae Less., respectively. However, the correct name of the tribe including
both Cichorium L., the type of the subfamily name Cichorioideae W. D. J. Koch (1837),
and Lactuca L. is Lactuceae Cass. (1815), not Cichorieae D. Don (1829), while that of the
subtribe including both Cichorium and Hyoseris L. is Hyoseridinae Less. (1832), not
Cichoriinae Sch. Bip. (1841) (unless the Cichoriaceae Juss. are accepted as a family dis-
tinct from Compositae).

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19-19A Subdivisions of families

19.5.  A name of a subdivision of a family based on an illegitimate generic
name that is not the base of a conserved family name is illegitimate. Con-
trary to Art. 32.1(b) such a name is validly published if it complies with
the other requirements for valid publication.

Ex. 5.  The name Caryophylloideae Arn. (1832), based on Caryophyllaceae Juss., nom.
cons.
, is legitimate although it is ultimately based on the illegitimate Caryophyllus Mill.
non L.

19.6.  When a name of a taxon assigned to one of the above categories has
been published with an improper Latin termination, such as -eae for a
subfamily or -oideae for a tribe, the termination must be changed to ac-
cord with the rule, without change of the author citation or date of publi-
cation (see Art. 32.5). However, if such names are published with a non-
Latin termination they are not validly published.

Ex. 6.  “Climacieae” (Grout, Moss Fl. N. Amer. 3: 4. 1928), published to designate a sub-
family
, is to be changed to Climacioideae Grout (1928).

Ex. 7.  However, Melantheen (Kittel in Richard, Nouv. Elém. Bot., ed. 3, Germ. Transl.:
727. 1840), published to designate a tribe, is not to be accepted as “Melanthieae Kitt.”, as it
has a German rather than a Latin termination. The name Melanthieae was validated later
by Grisebach (Spic. Fl. Rumel. 2: 377. 1846).

19.7.  When the Papilionaceae are included in the family Leguminosae
(nom. alt., Fabaceae; see Art. 18.5) as a subfamily, the name Papilionoi-
deae
may be used as an alternative to Faboideae.

Recommendation 19A

19A.1.  When a family is changed to the rank of a subdivision of a family, or the
inverse change occurs, and no legitimate name is available in the new rank, the
name should be retained, and only its termination (-aceae, -oideae, -eae, -inae)
altered.

Ex. 1.  The subtribe Drypetinae Griseb. (1859) (Euphorbiaceae) when raised to the rank of
tribe was named Drypeteae Hurus. (1954); the subtribe Antidesmatinae Müll. Arg. (1865)
(Euphorbiaceae) when raised to the rank of subfamily was named Antidesmatoideae
Hurus. (1954).

19A.2.  When a subdivision of a family is changed to another such rank, and no
legitimate name is available in the new rank, its name should be based on the
same generic name as the name in the former rank.

Ex. 2.  Three tribes of the family Ericaceae, none of which includes the type of that family
name (Erica L.), are Pyroleae D. Don, Monotropeae D. Don, and Vaccinieae D. Don. The
later names Pyroloideae A. Gray, Monotropoideae A. Gray, and Vaccinioideae Endl. are
based on the same generic names.

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Genera 20

SECTION 3. NAMES OF GENERA AND SUBDIVISIONS OF GENERA

Article 20

20.1.  The name of a genus is a noun in the nominative singular, or a word
treated as such, and is written with an initial capital letter (see Art. 60.2).
It may be taken from any source whatever, and may even be composed in
an absolutely arbitrary manner, but it must not end in -virus.

Ex. 1.  Rosa, Convolvulus, Hedysarum, Bartramia, Liquidambar, Gloriosa, Impatiens,
Rhododendron, Manihot, Ifloga
(an anagram of Filago).

20.2.  The name of a genus may not coincide with a technical term cur-
rently used in morphology unless it was published before 1 January 1912
and accompanied by a specific name published in accordance with the
binary system of Linnaeus.

Ex. 2.  “Radicula” (Hill, 1756) coincides with the technical term “radicula” (radicle) and
was not accompanied by a specific name in accordance with the binary system of Lin-
naeus. The name Radicula is correctly attributed to Moench (1794), who first combined it
with specific epithets.

Ex. 3.  Tuber F. H. Wigg. : Fr., when published in 1780, was accompanied by a binary
specific name (Tuber gulosorum F. H. Wigg.) and is therefore validly published.

Ex. 4.  The intended generic names “Lanceolatus” (Plumstead, 1952) and “Lobata”
(Chapman, 1952) coincide with technical terms and are therefore not validly published.

Ex. 5.  Words such as “radix”, “caulis”, “folium”, “spina”, etc., cannot now be validly
published as generic names.

20.3.  The name of a genus may not consist of two words, unless these
words are joined by a hyphen.

Ex. 6.  “Uva ursi”, as originally published by Miller (1754), consisted of two separate
words unconnected by a hyphen, and is therefore not validly published (Art. 32.1(b)); the
name is correctly attributed to Duhamel (1755) as Uva-ursi (hyphenated when published).

Ex. 7.  However, names such as Quisqualis L. (formed by combining two words into one
when originally published), Sebastiano-schaueria Nees, and Neves-armondia K. Schum.
(both hyphenated when originally published) are validly published.

Note 1.  The names of intergeneric hybrids are formed according to the provisions
of Art. H.6.

20.4.  The following are not to be regarded as generic names:

(a)  Words not intended as names.

Ex. 8.  The designation “Anonymos” was applied by Walter (Fl. Carol.: 2, 4, 9, etc. 1788)
to 28 different genera to indicate that they were without names.

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20-21 Genera – Subdivision of genera

Ex. 9.  “Schaenoides” and “Scirpoides”, as used by Rottbøll (Descr. Pl. Rar. Progr.: 14,
27. 1772) to indicate unnamed genera resembling Schoenus and Scirpus which he stated
(on p. 7) he intended to name later, are token words and not generic names. These un-
named genera were later legitimately named Kyllinga Rottb. and Fuirena Rottb.

(b)  Unitary designations of species.

Note 2.  Examples such as “Leptostachys” and “Anthopogon”, listed in pre-
Tokyo
editions of the Code, were from publications now listed in App. V.

Recommendation 20A

20A.1.  Authors forming generic names should comply with the following advice:

(a)   To use Latin terminations insofar as possible.

(b)   To avoid names not readily adaptable to the Latin language.

(c)   Not to make names which are very long or difficult to pronounce in Latin.

(d)   Not to make names by combining words from different languages.

(e)   To indicate, if possible, by the formation or ending of the name the affinities
       or analogies of the genus.

(f)   To avoid adjectives used as nouns.

(g)   Not to use a name similar to or derived from the epithet in the name of one of
       the species of the genus.

(h)   Not to dedicate genera to persons quite unconnected with botany or at least
       with natural science.

(i)   To give a feminine form to all personal generic names, whether they com-
       memorate a man or a woman (see Rec. 60B).

(j)   Not to form generic names by combining parts of two existing generic
       names, because such names are likely to be confused with nothogeneric
       names (see Art. H.6).

Ex. 1.  Hordelymus (K. Jess.) K. Jess. is based on Hordeum subg. Hordelymus K. Jess. The
subgeneric epithet was formed by combining parts of the generic names Hordeum L. and
Elymus L. (see also Art. H.3 Ex. 2).

Article 21

21.1.  The name of a subdivision of a genus is a combination of a generic
name and a subdivisional epithet. A connecting term (subgenus, sectio,
series, etc.) is used to denote the rank.

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Subdivisions of genera 21-21B

21.2.  The epithet is either of the same form as a generic name, or a noun
in the genitive plural, or a plural adjective agreeing in gender with the
generic name, but not noun in the genitive singular. It is written with an
initial capital letter (see Art. 32.5 and 60.2).

21.3.  The epithet in the name of a subdivision of a genus is not to be
formed from the name of the genus to which it belongs by adding the pre-
fix Eu-.

Ex. 1.  Costus subg. Metacostus; Ricinocarpos sect. Anomodiscus; Valeriana sect. Valeri-
anopsis;
Euphorbia sect. Tithymalus; Pleione subg. Scopulorum; Euphorbia subsect. Te-
nellae;
Sapium subsect. Patentinervia; Arenaria ser. Anomalae; but not Carex sect. Eu-
carex.

Note 1.  Names of subdivisions of the same genus, even if they differ in rank, are
homonyms if they have
the same epithet but are based on different types (Art.
53.4).

Note 2.  The names of hybrids with the rank of a subdivision of a genus are formed
according to the provisions of Art. H.7.

21.4.  The use of a binary combination instead of a subdivisional epithet is not
admissible. Contrary to Art. 32.1(b), names so constructed are validly pub-
lished but are to be altered to the proper form without change of author cita-
tion or date of publication.

Ex. 2.  Sphagnum “b. Sph. rigida” (Lindberg in Öfvers. Förh. Kongl. Svenska Vetensk.-
Akad. 19: 135. 1862) and S. sect. “Sphagna rigida” (Limpricht, Laubm. Deutschl. 1: 116.
1885) are to be cited as Sphagnum [unranked] Rigida Lindb. and S. sect. Rigida (Lindb.)
Limpr., respectively.

Recommendation 21A

21A.1.  When it is desired to indicate the name of a subdivision of the genus to
which a particular species belongs in connection with the generic name and spe-
cific epithet, the subdivisional epithet should be placed in parentheses between
the two; when desirable, the subdivisional rank may also be indicated.

21A.1.  Astragalus (Cycloglottis) contortuplicatus; A. (Phaca) umbellatus; Loranthus (sect.
Ischnanthus) gabonensis.

Recommendation 21B

21B.1.  The epithet in the name of a subgenus or section is preferably a noun,
that in the name of a subsection or lower subdivision of a genus preferably a
plural adjective.

21B.2.  Authors, when proposing new epithets for names of subdivisions of
genera, should avoid those in the form of a noun when other co-ordinate

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21B-22 Subdivisions of genera

subdivisions of the same genus have them in the form of a plural adjective, and
vice-versa. They should also avoid, when proposing an epithet for a name of a
subdivision of a genus, one already used for a subdivision of a closely related
genus, or one which is identical with the name of such a genus.

21B.3.  When a section or a subgenus is raised to the rank of genus, or the inverse
change occurs, the original name or epithet should be retained unless the resulting
name would be contrary to this Code.

Article 22

22.1.  The name of any subdivision of a genus that includes the type of the
adopted, legitimate name of the genus to which it is assigned is to repeat
that generic name unaltered as its epithet, not followed by an author cita-
tion
(see Art. 46). Such names are termed autonyms (Art. 6.8; see also
Art. 7.6).

Note 1.  This provision applies only to the names of those subordinate taxa that
include the type of the adopted name of the genus (but see Rec. 22A).

22.2.  A name of a subdivision of a genus that includes the type (i.e. the
original type or all elements eligible as type or the previously designated
type) of the adopted, legitimate name of the genus is not validly published
unless its epithet repeats the generic name unaltered. For the purposes of
this provision, explicit indication that the nomenclaturally typical element
is included is considered as equivalent to inclusion of the type, whether or
not it has been previously designated (see also Art. 21.3).

Ex. 1.  “Dodecatheon sect. Etubulosa” (Knuth in Engler, Pflanzenr. 22: 234. 1905) was
not validly published since it was proposed for a section that included D. meadia L., the
original type of the generic name Dodecatheon L.

Ex. 2.  Cactus [unranked] Melocactus L. (Gen. Pl., ed. 5: 210. 1754) was proposed for one
of four unranked (Art. 35.3), named subdivisions of the genus Cactus, comprising C. me-
locactus
L. (its type under Art. 22.6) and C. mammillaris L. It is validly published, even
though C. melocactus was subsequently designated as the type of Cactus L. (by Britton &
Millspaugh, Bahama Fl.: 294. 1920) and, later still, C. mammillaris became the conserved
type of the generic name (by the way in which the family name Cactaceae Juss. was con-
served).

22.3.  The first instance of valid publication of a name of a subdivision of
a genus under a legitimate generic name automatically establishes the
corresponding autonym (see also Art. 11.6 and 32.6).

Ex. 3.  The subgenus of Malpighia L. that includes the lectotype of the generic name
(M. glabra L.) is called M. subg. Malpighia, not M. subg. Homoiostylis Nied.; and the
section of Malpighia including the lectotype of the generic name is called M. sect. Malpi-
ghia,
not M. sect. Apyrae DC.

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Subdivisions of genera – Species 22-23

Ex. 4.  However, the correct name of the section of the genus Rhododendron L. that
includes R. luteum Sweet, the type of R. subg. Anthodendron (Rchb.) Rehder, is R. sect.
Pentanthera G. Don, the oldest legitimate name for the section, and not R. sect. Anthoden-
dron
.

22.4.  The epithet in the name of a subdivision of a genus may not repeat
unchanged the correct name of the genus, unless the two names have the
same type.

22.5.  The epithet in the name of a subdivision of a genus may not repeat
the generic name unaltered if the latter is illegitimate.

22.6.  When the epithet in the name of a subdivision of a genus is identical
with or derived from the epithet of one of its constituent species, the type
of the name of the subdivision of the genus is the same as that of the spe-
cies name, unless the original author of the subdivisional name designated
another type.

Ex. 5.  The type of Euphorbia subg. Esula Pers. is E. esula L.; the designation of E. peplus
L. as lectotype by Croizat (in Revista Sudamer. Bot. 6: 13. 1939) has no standing.

22.7.  When the epithet in the name of a subdivision of a genus is identical
with or derived from the epithet in a specific name that is a later homo-
nym, its type is the type of that later homonym, the correct name of which
necessarily has a different epithet.

Recommendation 22A

22A.1.  A section including the type of the correct name of a subgenus, but not
including the type of the correct name of the genus, should, where there is no
obstacle under the rules, be given a name with the same epithet and type as the
subgeneric name.

22A.2.  A subgenus not including the type of the correct name of the genus
should, where there is no obstacle under the rules, be given a name with the same
epithet and type as the correct name of one of its subordinate sections.

Ex. 1.  Instead of using a new epithet at the subgeneric level, Brizicky raised Rhamnus
sect. Pseudofrangula Grubov to the rank of subgenus as R. subg. Pseudofrangula (Grubov)
Brizicky. The type of both names is the same, R. alnifolia L’Hér.

SECTION 4. NAMES OF SPECIES

Article 23

23.1.  The name of a species is a binary combination consisting of the
name of the genus followed by a single specific epithet in the form of an

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23 Species

adjective, a noun in the genitive, or a word in apposition, or several words,
but not a phrase name of one or more descriptive nouns and associated
adjectives in the ablative (see Art. 23.6(a)), nor certain other irregularly
formed designations (see Art. 23.6(c)). If an epithet consists of two or
more words, these are to be united or hyphenated. An epithet not so joined
when originally published is not to be rejected but, when used, is to be
united or hyphenated, as specified in Art. 60.9.

23.2.  The epithet in the name of a species may be taken from any source
whatever, and may even be composed arbitrarily (but see Art. 60.1).

Ex. 1.  Cornus sanguinea, Dianthus monspessulanus, Papaver rhoeas, Uromyces fabae,
Fumaria gussonei, Geranium robertianum, Embelia sarasiniorum, Atropa bella-donna,
Impatiens noli-tangere, Adiantum capillus-veneris, Spondias mombin
(an indeclinable
epithet).

23.3.  Symbols forming part of specific epithets proposed by Linnaeus do
not invalidate the relevant names but must be transcribed.

Ex. 2.  Scandix pecten ♀ L. is to be transcribed as Scandix pecten-veneris; Veronica ana-
gallis
∇ L. is to be transcribed as Veronica anagallis-aquatica.

23.4.  The specific epithet, with or without the addition of a transcribed
symbol
, may not exactly repeat the generic name (such repetition would
result in a
tautonym).

Ex. 3.  “Linaria linaria” and “Nasturtium nasturtium-aquaticum” are contrary to this rule
and cannot be validly published.

Ex. 4.  Linum radiola L. (1753) when transferred to Radiola Hill may not be named “Ra-
diola radiola”,
as was done by Karsten (1882), since that combination is invalid (see Art.
32.1(b)). The next oldest name, L. multiflorum Lam. (1779), is illegitimate, being a super-
fluous name for L. radiola. Under Radiola, the species has been given the legitimate name
R. linoides Roth (1788).

23.5.  The specific epithet, when adjectival in form and not used as a
noun, agrees grammatically with the generic name; when it is a noun in
apposition or a genitive noun, it retains its own gender and termination
irrespective of the gender of the generic name. Epithets not conforming to
this rule are to be corrected (see Art. 32.5). In particular, the usage of the
word element -cola as an adjective is a correctable error.

Ex. 5.  Adjectival epithets: Helleborus niger L., Brassica nigra (L.) W. D. J. Koch, Ver-
bascum nigrum
L.; Vinca major L., Tropaeolum majus L.; Peridermium balsameum Peck,
derived from the epithet of Abies balsamea (L.) Mill., treated as an adjective.

Ex. 6.  Names with a noun for an epithet: Lythrum salicaria L., Convolvulus cantabrica L.,
Gentiana pneumonanthe L., all with epithets featuring pre-Linnaean generic names.

Gloeosporium balsameae Davis, derived from the epithet of Abies balsamea (L.) Mill.,
treated as a noun.

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Species 23

Ex. 7.  Correctable errors: The epithet of Polygonum segetum Kunth (1817) is a genitive
plural noun (of the corn fields); the combination Persicaria “segeta”, proposed by Small,
is a correctable error for Persicaria segetum (Kunth) Small (1903).  –  In Masdevallia
echidna Rchb. f. (1855), the epithet corresponds to the generic name of an animal; upon
transfer to Porroglossum Schltr., the combination P. “echidnum” was proposed by Garay,
which is a correctable error for P. echidna (Rchb. f.) Garay (1953).

Ex. 8.  Rubus “amnicolus” is a correctable error for R. amnicola Blanch. (1906).

23.6.  The following designations are not to be regarded as specific names:

(a)  Descriptive designations consisting of a generic name followed by a
       phrase name (Linnaean nomen specificum legitimum) of one or
       more descriptive nouns and associated adjectives in the ablative.

Ex. 9.  Smilax “caule inermi” (Aublet, Hist. Pl. Guiane 2, Tabl.: 27. 1775) is an abbrevi-
ated descriptive reference to an imperfectly known species which is not given a binomial
in the text but referred to merely by a phrase name cited from Burman.

(b)  Other designations of species consisting of a generic name followed
       by one or more words not intended as a specific epithet.

Ex. 10.  Viola “qualis” (Krocker, Fl. Siles. 2: 512, 517. 1790); Urtica “dubia?” (Forsskål,
Fl. Aegypt.-Arab.: cxxi. 1775), the word “dubia?” being repeatedly used in Forsskål’s
work for species which could not be reliably identified.

Ex. 11.  Atriplex “nova” (Winterl, Index Hort. Bot. Univ. Hung.: fol. A [8] recto et verso.
1788), the word “nova” (new) being here used in connection with four different species of
Atriplex. However, in Artemisia nova A. Nelson (in Bull. Torrey Bot. Club 27: 274. 1900),
nova was intended as a specific epithet, the species having been newly distinguished from
others.

Ex. 12.  Cornus “gharaf” (Forsskål, Fl. Aegypt.-Arab.: xci, xcvi. 1775) is an interim des-
ignation not intended as a species name. An interim designation in Forsskål’s work is an
original designation (for an accepted taxon and thus not a “provisional name” as defined in
Art. 34.1(b)) with an epithet-like vernacular which is not used as an epithet in the “Centu-
riae” part of the work. Elcaja “roka” (Forsskål, Fl. Aegypt.-Arab.: xcv. 1775) is another
example of such an interim designation; in other parts of the work (p. c, cxvi, 127) this
species is not named.

Ex. 13.  In Agaricus “octogesimus nonus” and Boletus “vicesimus sextus” (Schaeffer,
Fung. Bavar. Palat. Nasc. 1: t. 100. 1762; 2: t. 137. 1763), the generic names are followed
by ordinal adjectives used for enumeration. The corresponding species were given valid
names, A. cinereus Schaeff. and B. ungulatus Schaeff., in the final volume of the same
work (1774).

Ex. 14.  Honckeny (1782; see Art. 46 Ex. 27) used species designations such as, in
Agrostis, “A. Reygeri I.”, A. Reyg. II.”, “A. Reyg. III.” (all referring to species described but
not named in Reyger, Tent. Fl. Gedan.: 36-37. 1763), and also “A. alpina. II” for a newly
described species following after A. alpina Scop. These are informal designations used for
enumeration, not validly published binomials; they may not be expanded into, e.g., “Agro-
stis reygeri-prima”
.

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23-23A Species

(c)  Designations of species consisting of a generic name followed by two
       or more adjectival words in the nominative case.

Ex. 15.  Salvia “africana coerulea” (Linnaeus, Sp. Pl.: 26. 1753) and Gnaphalium “fruti-
cosum flavum”
(Forsskål, Fl. Aegypt.-Arab.: cxix. 1775) are generic names followed by
two adjectival words in the nominative case. They are not to be regarded as species names.

Ex. 16.  However, Rhamnus “vitis idaea” Burm. f. (Fl. Ind.: 61. 1768) is to be regarded as
a species name, since the generic name is followed by a noun and an adjective, both in the
nominative case; these words are to be hyphenated (R. vitis-idaea) under the provisions of
Art. 23.1 and Art. 60.9. In Anthyllis “Barba jovis” L. (Sp. Pl.: 720. 1753) the generic name
is followed by nouns in the nominative and in the genitive case, respectively, and they are
to be hyphenated (A. barba-jovis). Likewise, Hyacinthus “non scriptus” L. (Sp. Pl.: 316.
1753), where the generic name is followed by a negative particle and a past participle used
as an adjective, is corrected to H. non-scriptus, and Impatiens “noli tangere” L. (Sp. Pl.:
938. 1753), where the generic name is followed by two verbs, is corrected to I. noli-tan-
gere
.

Ex. 17.  Similarly, in Narcissus “Pseudo Narcissus” L. (Sp. Pl.: 289. 1753) the generic
name is followed by an independent prefix and a noun in the nominative case, and the
name is to be corrected to N. pseudonarcissus under the provisions of Art. 23.1 and Art.
60.9.

(d)  Formulae designating hybrids (see Art. H.10.3).

23.7.  Phrase names used by Linnaeus as specific epithets (nomina trivia-
lia
)
are to be corrected in accordance with later usage by Linnaeus him-
self.

Ex. 18.  Apocynum “fol. [foliis] androsaemi” L. is to be cited as A. androsaemifolium L.
(Sp. Pl.: 213. 1753 [corr. L., Syst. Nat., ed. 10, 2: 946. 1759]); and Mussaenda “fr. [fructu]
frondoso” L., as M. frondosa L. (Sp. Pl.: 177. 1753 [corr. L., Syst. Nat., ed. 10, 2: 931.
1759]).

23.8.  Where the status of a designation of a species is uncertain under
Art. 23.6, established custom is to be followed (Pre. 10).

*Ex. 19.  Polypodium “F. mas”, P. “F. femina”, and P. “F. fragile” (Linnaeus, Sp. Pl.:
1090-1091. 1753) are, in accordance with established custom, to be treated as P. filix-mas
L., P. filix-femina L., and P. fragile L., respectively. Likewise, Cambogia “G. gutta” is to
be treated as C. gummi-gutta L. (Gen. Pl.: [522]. 1754). The intercalations “Trich.”
[Trichomanes] and “M.” [Melilotus] in the names of Linnaean species of Asplenium and
Trifolium, respectively, are to be deleted, so that names in the form Asplenium “Trich.
dentatum”
and Trifolium “M. indica”, for example, are treated as A. dentatum L. and T.
indicum
L. (Sp. Pl.: 765, 1080. 1753).

Recommendation 23A

23A.1.  Names of persons and also of countries and localities used in specific
epithets should take the form of nouns in the genitive (clusii, porsildiorum, sa-
harae)
or of adjectives (clusianus, dahuricus) (see also Art. 60, Rec. 60C and D).

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Species - Infraspecific taxa 23A-24

23A.2.  The use of the genitive and the adjectival form of the same word to desig-
nate two different species of the same genus should be avoided (e.g. Lysimachia
hemsleyana
Oliv. and L. hemsleyi Franch.).

23A.3.  In forming specific epithets, authors should comply also with the follow-
ing suggestions:

(a)  To use Latin terminations insofar as possible.

(b)  To avoid epithets which are very long and difficult to pronounce in Latin.

(c)  Not to make epithets by combining words from different languages.

(d)  To avoid those formed of two or more hyphenated words.

(e)  To avoid those which have the same meaning as the generic name (pleo-
       nasm).

(f)  To avoid those which express a character common to all or nearly all the
       species of a genus.

(g)  To avoid in the same genus those which are very much alike, especially those
       which differ only in their last letters or in the arrangement of two letters.

(h)  To avoid those which have been used before in any closely allied genus.

(i)   Not to adopt epithets from unpublished names found in correspondence,
       travellers’ notes, herbarium labels, or similar sources, attributing them to
       their authors, unless these authors have approved publication (see Rec. 34A).

(j)   To avoid using the names of little-known or very restricted localities unless
       the species is quite local.

SECTION 5. NAMES OF TAXA BELOW THE RANK OF SPECIES

(INFRASPECIFIC TAXA)

Article 24

24.1.  The name of an infraspecific taxon is a combination of the name of
a species and an infraspecific epithet. A connecting term is used to denote
the rank.

Ex. 1.  Saxifraga aizoon subf. surculosa Engl. & Irmsch. This taxon may also be referred
to
as Saxifraga aizoon var. aizoon subvar. brevifolia f. multicaulis subf. surculosa Engl. &
Irmsch.; in this way a full classification of the subforma within the species is given, not
only its name
.

24.2.  Infraspecific epithets are formed like specific epithets and, when
adjectival in form and not used as nouns, they agree grammatically with
the generic name (see Art. 32.5).

Ex. 2.  Solanum melongena var. insanum Prain (Bengal Pl.: 746. 1903, “insana”).

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24-25 Infraspecific taxa

24.3.  Infraspecific names with final epithets such as typicus, originalis,
originarius, genuinus, verus,
and veridicus, purporting to indicate the
taxon containing the type of the name of the next higher taxon, are not
validly published unless they are autonyms (Art. 26).

Ex. 3.  Lobelia spicata “var. originalis” (McVaugh in Rhodora 38: 308. 1936) was not
validly published (see Art. 26 Ex. 1).

24.4.  The use of a binary combination instead of an infraspecific epithet
is not admissible. Contrary to Art. 32.1(b), names so constructed are val-
idly published but are to be altered to the proper form without change of
the author citation or date of publication.

Ex. 4.  Salvia grandiflora subsp. “S. willeana” (Holmboe in Bergens Mus. Skr., ser. 2,
1(2): 157. 1914) is to be cited as S. grandiflora subsp. willeana Holmboe.

Ex. 5.  Phyllerpa prolifera var. “Ph. firma” (Kützing, Sp. Alg.: 495. 1849) is to be altered
to P. prolifera var. firma Kütz.

Note 1.  Infraspecific taxa within different species may bear names with the same
final epithet; those within one species may bear names with the same final epithet
as the names of other species (but see Rec. 24B.1).

Ex. 6.  Rosa glutinosa var. leioclada H. Christ (in Boissier, Fl. Orient. Suppl.: 222. 1888)
and Rosa jundzillii f. leioclada Borbás (in Math. Term. Közlem. 16: 376, 383. 1880) are
both permissible, as is Viola tricolor var. hirta Ging. (in Candolle, Prodr. 1: 304. 1824), in
spite of the previous existence of a species named Viola hirta L.

Note 2.  Names of infraspecific taxa within the same species, even if they differ in
rank, are homonyms if they have the same epithet but are based on different types
(Art. 53.4).

Recommendation 24A

24A.1.  Recommendations made for forming specific epithets (Rec. 23A) apply
equally for infraspecific epithets.

Recommendation 24B

24B.1.  Authors proposing new infraspecific names should avoid epithets previ-
ously used as specific epithets in the same genus.

24B.2.  When an infraspecific taxon is raised to the rank of species, or the inverse
change occurs, the final epithet of its name should be retained unless the resulting
combination would be contrary to this Code.

Article 25

25.1.  For nomenclatural purposes, a species or any taxon below the rank
of species is regarded as the sum of its subordinate taxa, if any. In fungi, a
holomorph also includes its correlated form-taxa (see Art. 59).

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Infraspecific taxa 25-26

Ex. 1.  When Montia parvifolia (DC.) Greene is treated as comprising two subspecies, one
must write M. parvifolia subsp. parvifolia for that part of the species that includes the
nomenclatural type and excludes the type of the name of the other subspecies, M. parvi-
folia
subsp. flagellaris (Bong.) Ferris. The name M. parvifolia applies to the species in its
entirety.

Article 26

26.1.  The name of any infraspecific taxon that includes the type of the
adopted, legitimate name of the species to which it is assigned is to repeat
the specific epithet unaltered as its final epithet, not followed by an author
citation (see Art. 46). Such names are termed autonyms (Art. 6.8; see also
Art. 7.6).

Ex. 1.  The variety which includes the type of the name Lobelia spicata Lam. is to be
named Lobelia spicata Lam. var. spicata (see also Art. 24 Ex. 3).

Note 1.  This provision applies only to the names of those subordinate taxa that
include the type of the adopted name of the species (but see Rec. 26A).

26.2.  A name of an infraspecific taxon that includes the type (i.e. the
holotype or all syntypes or the previously designated type) of the adopted,
legitimate name of the species to which it is assigned is not validly pub-
lished unless its final epithet repeats the specific epithet unaltered. For the
purpose of this provision, explicit indication that the nomenclaturally
typical element of the species is included is considered as equivalent to
inclusion of the type, whether or not it has been previously designated
(see also Art. 24.3).

Ex. 2.  The intended combination “Vulpia myuros subsp. pseudomyuros (Soy.-Will.) Maire
& Weiller” was not validly published in Maire (Fl. Afrique N. 3: 177. 1955) because it
included “F. myuros L., Sp. 1, p. 74 (1753) sensu stricto” in synonymy, Festuca myuros L.
being the basionym of Vulpia myuros (L.) C. C. Gmel.

Ex. 3.  Linnaeus (Sp. Pl.: 3. 1753) recognized two named varieties under Salicornia eu-
ropaea
. Since S. europaea has no holotype and no syntypes are cited, both varietal names
are validly published irrespective of the facts that the lectotype of S. europaea, designated
by Jafri and Rateeb (in Jafri & El-Gadi, Fl. Libya 58: 57. 1979), can be attributed to S. eu-
ropaea
var. herbacea L. (1753) and that the latter name was subsequently lectotypified by
Piirainen (in Ann. Bot. Fenn. 28: 82. 1991) by the same specimen as the species name.

Ex. 4.  Linnaeus (Sp. Pl.: 779-781. 1753) recognized 13 named varieties under Medicago
polymorpha
. Since M. polymorpha L. has neither a holotype nor syntypes, all varietal
names are validly published, and indeed the lectotype subsequently designated (by Heyn in
Bull. Res. Council Israel, Sect. D, Bot., 7: 163. 1959) is not part of the original material for
any of the varietal names of 1753
.

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7 Infraspecific taxa

26.3.  The first instance of valid publication of a name of an infraspecific
taxon under a legitimate species name automatically establishes the corre-
sponding autonym (see also Art. 32.6 and 11.6).

Ex. 5.  The publication of the name Lycopodium inundatum var. bigelovii Tuck. (in Amer.
J. Sci. Arts 45: 47. 1843) automatically established the name of another variety, L. inun-
datum
L. var. inundatum, the type of which is that of the name L. inundatum L.

Ex. 6.  Utricularia stellaris L. f. (1782) includes U. stellaris var. coromandeliana A. DC.
(Prodr. 8: 3. 1844) and U. stellaris L. f. var. stellaris (1844) automatically established at
the same time. When U. stellaris is included in U. inflexa Forssk. (1775) as a variety, the
correct name of that variety, under Art. 11.6, is U. inflexa var. stellaris (L. f.) P. Taylor
(1961).

Ex. 7.  Pangalo (in Trudy Prikl. Bot. 23: 258. 1930) when describing Cucurbita mixta
Pangalo distinguished two varieties, C. mixta var. cyanoperizona Pangalo and var. steno-
sperma
Pangalo, together encompassing the entire circumscription of the species. Since
neither a holotype nor any syntypes were indicated for C. mixta, both varietal names were
validly published (see Art. 26.2). Merrick & Bates (in Baileya 23: 96, 101. 1989), in the
absence of known type material, neotypified C. mixta by an element that can be attributed
to C. mixta var. stenosperma. As long as their choice of neotype is followed, the correct
name for that variety is C. mixta var. mixta, not C. mixta var. stenosperma. When it is
treated as a variety of C. argyrosperma Huber (1867), as by Merrick & Bates, its correct
name under Art. 11.6 is not C. argyrosperma var. stenosperma (Pangalo) Merrick & D. M.
Bates; a combination based on C. mixta is required.

Recommendation 26A

26A.1.  A variety including the type of the correct name of a subspecies, but not
including the type of the correct name of the species, should, where there is no
obstacle under the rules, be given a name with the same final epithet and type as
the subspecies name.

26A.2.  A subspecies not including the type of the correct name of the species
should, where there is no obstacle under the rules, be given a name with the same
final epithet and type as a name of one of its subordinate varieties.

26A.3.  A taxon of rank lower than variety which includes the type of the correct
name of a subspecies or variety, but not the type of the correct name of the spec-
ies, should, where there is no obstacle under the rules, be given a name with the
same final epithet and type as the name of the subspecies or variety. On the other
hand, a subspecies or variety which does not include the type of the correct name
of the species should not be given a name with the same final epithet as a name of
one of its subordinate taxa below the rank of variety.

Ex. 1.  Fernald treated Stachys palustris subsp. pilosa (Nutt.) Epling (in Repert. Spec. Nov.
Regni Veg. Beih. 8: 63. 1934) as composed of five varieties, for one of which (that in-
cluding the type of S. palustris subsp. pilosa) he made the combination S. palustris var.
pilosa (Nutt.) Fernald (in Rhodora 45: 474. 1943), there being no legitimate varietal name
available.

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Infraspecific taxa – Cultivated plants 26A-28

Ex. 2.  There being no legitimate name available at the rank of subspecies, Bonaparte made
the combination Pteridium aquilinum subsp. caudatum (L.) Bonap. (Notes Ptérid. 1: 62.
1915), using the same final epithet that Sadebeck had used earlier in the combination
P. aquilinum var. caudatum (L.) Sadeb. (in Jahrb. Hamburg. Wiss. Anst. Beih. 14(3): 5.
1897), both combinations being based on Pteris caudata L. Each name is legitimate, and
both can be used, as by Tryon (in Rhodora 43: 52-54. 1941), who treated P. aquilinum var.
caudatum as one of four varieties under subsp. caudatum (see Art. 34.2).

Article 27

27.1.  The final epithet in the name of an infraspecific taxon may not re-
peat unchanged the epithet of the correct name of the species to which the
taxon is assigned unless the two names have the same type.

27.2.  The final epithet in the name of an infraspecific taxon may not re-
peat unchanged the epithet of the species name if that species name is
illegitimate.

SECTION 6. NAMES OF PLANTS IN CULTIVATION

Article 28

28.1.  Plants brought from the wild into cultivation retain the names that
are applied to the same taxa growing in nature.

Note 1.  Hybrids, including those arising in cultivation, may receive names as
provided in App. I (see also Art. 11.8, 40, and 50).

Note 2.  Additional, independent designations for special categories of plants used
in agriculture, forestry, and horticulture (and arising either in nature or cultiva-
tion) are dealt with in the International code of nomenclature for cultivated
plants,
where the term “cultivar” is defined and regulations are provided for the
formation and use of cultivar epithets.

Note 3.  Nothing precludes the use, for cultivated plants, of names published in
accordance with the requirements of the botanical Code.

Note 4.  Epithets in names published in conformity with the botanical Code may
be used as cultivar epithets under the rules of the International code of nomen-
clature for cultivated plants,
when cultivar is considered to be the appropriate
status for the groups concerned.

Ex. 1.  Mahonia japonica DC. (1821) may be treated as a cultivar, which is then desig-
nated as Mahonia ‘Japonica’; Taxus baccata var. variegata Weston (1770), when treated
as a cultivar, is designated as
Taxus baccata ‘Variegata’.

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28 Cultivated plants

Note 5.  The International code of nomenclature for cultivated plants provides for
the establishment of cultivar epithets differing markedly from epithets in Latin
form
.

Ex. 2.  ×Disophyllum ‘Frühlingsreigen’; Eriobotrya japonica ‘Golden Ziad’ and E. japonica
‘Maamora Golden Yellow’; Phlox drummondii ‘Sternenzauber’; Quercus frainetto ‘Hun-
garian Crown’

Ex. 3.  Juniperus ×pfitzeriana ‘Wilhelm Pfitzer’ (P. A. Schmidt 1998) was established for
a tetraploid cultivar presumed to result from the original cross between J. chinensis L. and
J. sabina L.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Effective publication 29-30

 
 
 
 

CHAPTER IV. EFFECTIVE AND VALID PUBLICATION

SECTION 1. CONDITIONS AND DATES OF EFFECTIVE PUBLICATION

Article 29

29.1.  Publication is effected, under this Code, only by distribution of
printed matter (through sale, exchange, or gift) to the general public or at
least to botanical institutions with libraries accessible to botanists gener-
ally. It is not effected by communication of new names at a public meet-
ing, by the placing of names in collections or gardens open to the public,
by the issue of microfilm made from manuscripts, typescripts or other
unpublished material, by publication online, or by dissemination of dis-
tributable electronic media.

Ex. 1.  Cusson announced his establishment of the genus Physospermum in a memoir read
at the Société des Sciences de Montpellier in 1770, and later in 1782 or 1783 at the Société
de Médecine de Paris, but its effective publication dates from 1787 (in Hist. Soc. Roy.
Méd. 5(1): 279).

Article 30

30.1.  Publication by indelible autograph before 1 January 1953 is effec-
tive. Indelible autograph produced at a later date is not effectively pub-
lished.

Ex. 1.  Salvia oxyodon Webb & Heldr. was effectively published in an indelible autograph
catalogue placed on sale (Webb & Heldreich, Catalogus plantarum hispanicarum ... ab A.
Blanco lectarum,
Paris, Jul 1850, folio).

Ex. 2.  The Journal of the International Conifer Preservation Society, vol. 5[1]. 1997
(“1998”), consists of duplicated sheets of typewritten text with handwritten additions and
corrections in several places. The handwritten portions, being indelible autograph pub-
lished after 1 January 1953, are not effectively published. Intended new combinations
(“Abies koreana var. yuanbaoshanensis”, p. 53) for which the basionym reference is
handwritten are not validly published. The entirely handwritten account of a new taxon
(p. 61: name, Latin description, statement of type) is treated as unpublished (see also Rec.
34A.1).

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30-30A Effective publication

30.2.  For the purpose of this Article, indelible autograph is handwritten
material reproduced by some mechanical or graphic process (such as li-
thography, offset, or metallic etching).

Ex.3.  Léveillé, Flore du Kouy Tchéou (1914-1915), is a work lithographed from a hand-
written text.

30.3.  Publication on or after 1 January 1953 in trade catalogues or non-
scientific newspapers, and on or after 1 January 1973 in seed-exchange
lists, does not constitute effective publication.

30.4.  The distribution on or after 1 January 1953 of printed matter ac-
companying exsiccata does not constitute effective publication.

Note 1.  If the printed matter is also distributed independently of the exsiccata, it
is effectively published.

Ex. 4.  The printed labels of Fuckel’s Fungi rhenani exsiccati (1863-1874) are effectively
published even though not independently issued. The labels antedate Fuckel’s subsequent
accounts (e.g., in Jahrb. Nassauischen Vereins Naturk. 23-24. 1870).

Ex. 5.  Vězda’s Lichenes selecti exsiccati (1967-) were issued with printed labels that were
also distributed independently as printed fascicles; the latter are effectively published and
new names appearing in Vězda’s exsiccata are to be cited from the fascicles.

Recommendation 30A

30A.1.  It is strongly recommended that authors avoid publishing new names and
descriptions or diagnoses of new taxa in ephemeral printed matter of any kind, in
particular printed matter that is multiplied in restricted and uncertain numbers, in
which
the permanence of the text may be limited, for which effective publication
in terms of number of copies is not obvious, or that is unlikely to reach the gen-
eral public. Authors should also avoid publishing new names and descriptions or
diagnoses in popular periodicals, in abstracting journals, or on correction slips.

Ex. 1.  Kartesz provided an unpaged, printed insert titled “Nomenclatural innovations” to
accompany the electronic version (1.0) of the Synthesis of the North American flora pro-
duced on compact disk (CD-ROM; a distributable electronic medium in terms of Art
29.1). This insert, which is effectively published under Art. 29-30, is the place of valid
publication of 41 new combinations, which also appear on the disk, in an item authored by
Kartesz: “A synonymized checklist and atlas with biological attributes for the vascular
flora of the United States, Canada, and Greenland” (e.g., Dichanthelium hirstii (Swallen)
Kartesz in Kartesz & Meacham, Synth. N. Amer. Fl., Nomencl. Innov.: [1]. Aug 1999).
Kartesz’s procedure is not to be recommended, as the insert is unlikely to be permanently
stored and catalogued in botanical libraries and so reach the general public.

30A.2.  Authors publishing nomenclatural novelties should give preference to
periodicals that regularly publish taxonomic articles, or else they should send a
copy of their work to the appropriate indexing centre(s).

30A.3.  Authors and editors are encouraged to mention nomenclatural novelties in
the summary or abstract, or list them in an index in the publication.

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Effective publication – Valid publication 31-32

Article 31

31.1.  The date of effective publication is the date on which the printed
matter became available as defined in Art. 29 and 30. In the absence of
proof establishing some other date, the one appearing in the printed matter
must be accepted as correct.

Ex. 1.  Individual parts of Willdenow’s Species plantarum were published as follows: 1(1),
Jun 1797; 1(2), Jul 1798; 2(1), Mar 1799; 2(2), Dec 1799; 3(1), 1800; 3(2), Nov 1802;
3(3), Apr-Dec 1803; 4(1), 1805; 4(2), 1806; these dates are presently accepted as the dates
of effective publication (see Stafleu & Cowan in Regnum Veg. 116: 303. 1988).

Ex. 2.  T. M. Fries first published Lichenes arctoi in 1860 as an independently paginated
preprint, which predates the identical version published in a journal (Nova Acta Reg. Soc.
Sci. Upsal. ser. 3, 3: 103-398. 1861).

31.2.  When separates from periodicals or other works placed on sale are
issued in advance, the date on the separate is accepted as the date of ef-
fective publication unless there is evidence that it is erroneous.

Ex. 3.  The names of the Selaginella species published by Hieronymus (in Hedwigia 51:
241-272) were effectively published on 15 October 1911, since the volume in which the
paper appeared, though dated 1912, states (p. ii) that the separate appeared on that date.

Recommendation 31A

31A.1.  The date on which the publisher or publisher’s agent delivers printed
matter to one of the usual carriers for distribution to the public should be accepted
as its date of effective publication.

SECTION 2. CONDITIONS AND DATES OF VALID PUBLICATION OF

NAMES

Article 32

32.1.  In order to be validly published, a name of a taxon (autonyms ex-
cepted) must: (a) be effectively published (see Art. 29-31) on or after the
starting-point date of the respective group (Art. 13.1); (b) have a form
which complies with the provisions of Art. 16-27 (but see Art. 18.3, 19.5,
and 24.4), and Art. H.6 and H.7; (c) be accompanied by a description or
diagnosis or by a reference to a previously and effectively published de-
scription or diagnosis (except as provided in Art. 42.3, 44.1, and H.9); and
(d) comply with the special provisions of Art. 33-45 (see also Art. 61).

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Valid publication 32

Ex. 1.  “Egeria” (Néraud in Gaudichaud, Voy. Uranie, Bot.: 25, 28. 1826), published
without a description or a diagnosis or a reference to a former one, was not validly pub-
lished.

Ex. 2.  Loranthus macrosolen Steud.” originally appeared without a description or diag-
nosis on the printed labels issued about the year 1843 with Sect. II, No. 529, 1288, of
Schimper’s herbarium specimens of Abyssinian plants; the name was not validly pub-
lished, however, until Richard (Tent. Fl. Abyss. 1: 340. 1847) supplied a description.

*Ex. 3.  In Don, Sweet’s Hortus britannicus, ed. 3 (1839), for each listed species the flower
colour, the duration of the plant, and a translation into English of the specific epithet are
given in tabular form. In many genera the flower colour and duration may be identical for all
species and clearly their mention is not intended as a validating description or diagnosis. New
names appearing in that work are therefore not validly published, except in some cases where
reference is made to earlier descriptions or diagnoses or to validly published basionyms.

32.2.  A diagnosis of a taxon is a statement of that which in the opinion of
its author distinguishes the taxon from others.

32.3.  For the purpose of valid publication of a name, reference to a previ-
ously and effectively published description or diagnosis may be direct or
indirect (Art. 32.4). For names published on or after 1 January 1953 it
must, however, be full and direct as specified in Art. 33.3.

32.4.  An indirect reference is a clear (if cryptic) indication, by an author
citation
or in some other way, that a previously and effectively published
description or diagnosis applies.

Ex. 4.  “Kratzmannia” (Opiz in Berchtold & Opiz, Oekon.-Techn. Fl. Böhm. 1: 398. 1836)
was published with a diagnosis but was not definitely accepted by the author and therefore
was not validly published. Kratzmannia Opiz (Seznam: 56. 1852), lacking description or
diagnosis, is however definitely accepted, and its citation as “Kratzmannia O.” constitutes
indirect reference to the diagnosis published in 1836.

Ex. 5.  Opiz published the name of the genus Hemisphace (Benth.) Opiz (1852) without a
description or diagnosis, but as he wrote “Hemisphace Benth.” he indirectly referred to the
previously effectively published description by Bentham (Labiat. Gen. Spec.: 193. 1833)
of Salvia sect. Hemisphace.

Ex. 6.  The new combination Cymbopogon martini (Roxb.) W. Watson (1882) is validated
by the addition of the number “309”, which, as explained at the top of the same page, is the
running-number of the species (Andropogon martini Roxb.) in Steudel (Syn. Pl. Glumac.
1: 388. 1854). Although the reference to the basionym Andropogon martini is indirect, it is
unambiguous (but see Art. 45 Ex. 1; see also Rec. 60C.2).

Ex. 7.  Miller (1768), in the preface to The gardeners dictionary, ed. 8, stated that he had
“now applied Linnaeus’s method entirely except in such particulars ...”, of which he gave
examples. In the main text, he often referred to Linnaean genera under his own generic
headings, e.g., to Cactus L. [pro parte] under Opuntia Mill. Therefore an implicit reference to a
Linnaean binomial may be assumed when this is appropriate, and Miller’s binomials are then
accepted as new combinations (e.g., Opuntia ficus-indica (L.) Mill., based on Cactus ficus-
indica
L.) or nomina nova (e.g., Opuntia vulgaris Mill., based on Cactus opuntia L.: both
names have the reference to “Opuntia vulgo herbariorum” of Bauhin & Cherler in common).

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Valid publication 32-32C

Ex. 8.  In Kummer’s Führer in die Pilzkunde (1871) the statement that the author intended
to adopt at generic rank the subdivisions of Agaricus then in use, which at the time were
those of Fries, and the general arrangement of the work, which faithfully follows that of
Fries, provide indirect reference to Fries’s earlier names of “tribes”. Therefore, names such
as Hypholoma (Fr. : Fr.) P. Kumm. are accepted as being based on the corresponding
Friesian names (here: A. “tribus” Hypholoma Fr. : Fr.) although Kummer did not explicitly
refer to Fries.

32.5.  Names or epithets published with an incorrect Latin termination but
otherwise in accordance with this Code are regarded as validly published;
they are to be changed to accord with Art. 17-20, 21, 23, and 24, without
change of the author citation or date of publication (see also Art. 60.11).

32.6.  Autonyms (Art. 6.8) are accepted as validly published names, dat-
ing from the publication in which they were established (see Art. 22.3 and
26.3), whether or not they appear in print in that publication.

32.7.  Names in specified ranks included in publications listed as sup-
pressed works (opera utique oppressa; App. V) are not validly published.
Proposals for the addition of publications to App. V must be submitted to
the General Committee (see Div. III), which will refer them for examina-
tion to the committees for the various taxonomic groups (see Rec. 32F;
see also Art. 14.14 and Rec. 14A).

32.8.  When a proposal for the suppression of a publication as been ap-
proved by the General Committee after study by the committees for the
taxonomic groups concerned, suppression of that publication is authorized
subject to the decision of a later International Botanical Congress.

Note. 1.  For valid publication of names of plant taxa that were originally not
treated as plants, see Art. 45.4.

Recommendation 32A

32A.1.  A name should not be validated solely by a reference to a description or
diagnosis published before 1753.

Recommendation 32B

32B.1.  The description or diagnosis of any new taxon should mention the points
in which the taxon differs from its allies.

Recommendation 32C

32C.1.  When naming a new taxon, authors should not adopt a name that has been
previously but not validly published for a different taxon.

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32D-33 Valid publication

Recommendation 32D

32D.1.  In describing or diagnosing new taxa, authors should, when possible,
supply figures with details of structure as an aid to identification.

32D.2.  In the explanation of the figures, authors should indicate the specimen(s)
on which they are based (see also Rec. 8A.2).

32D.3.  Authors should indicate clearly and precisely the scale of the figures
which they publish.

Recommendation 32E

32E.1.  Descriptions or diagnoses of parasitic plants should always be followed
by indication of the hosts, especially those of parasitic fungi. The hosts should be
designated by their scientific names and not solely by names in modern lan-
guages, the applications of which are often doubtful.

Recommendation 32F

32F.1.  When a proposal for the suppression of a publication under Art. 32.7 has
been referred to the appropriate committees for study, authors should follow
existing usage as far as possible pending the General Committee’s recommenda-
tion on the proposal.

Article 33

33.1.  A combination (autonyms excepted) is not validly published unless
the author definitely associates the final epithet with the name of the ge-
nus or species, or with its abbreviation.

Ex. 1.  Combinations validly published: In Linnaeus’s Species plantarum the placing of the
epithet in the margin opposite the name of the genus clearly associates the epithet with the
name of the genus. The same result is attained in Miller’s Gardeners dictionary, ed. 8, by
the inclusion of the epithet in parentheses immediately after the name of the genus, in
Steudel’s Nomenclator botanicus by the arrangement of the epithets in a list headed by the
name of the genus, and in general by any typographical device which associates an epithet
with a particular generic or specific name.

Ex. 2.  Combinations not validly published: Rafinesque’s statement under Blephilia that
“Le type de ce genre est la Monarda ciliata Linn.” (in J. Phys. Chim. Hist. Nat. Arts 89:
98. 1819) does not constitute valid publication of the combination B. ciliata, since Rafi-
nesque did not definitely associate the epithet ciliata with the generic name Blephilia.
Similarly, the combination Eulophus peucedanoides is not to be attributed to Bentham &
Hooker (Gen. Pl. 1: 885. 1867) on the basis of their listing of “Cnidium peucedanoides,
H. B. et K.” under Eulophus.

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Valid publication 33

33.2.  If, for a presumed new combination, no reference to a basionym is
given but the epithet of a previously and validly published name that ap-
plies to the same taxon is adopted, the new combination is validly pub-
lished as such if, and only if, it would otherwise be validly published as
the name of a new taxon (see also Art. 33.6(d)).

Ex. 3.  Scaevola taccada was validly published by Roxburgh (1814) by reference to an
illustration in Rheede (Hort. Malab. 4: t. 59. 1683) that appears to be its sole basis. As the
name applies to the species previously described as Lobelia taccada Gaertn. (1788), it is
treated as a new combination, S. taccada (Gaertn.) Roxb., not as the name of a new spe-
cies, even though Gaertner is not referred to in Roxburgh’s protologue.

33.3.  A new combination, or an avowed substitute (replacement name,
nomen novum), published on or after 1 January 1953 based on a previ-
ously and validly published name is not validly published unless its ba-
sionym (name-bringing or epithet-bringing synonym) or the replaced
synonym (when a new name is proposed) is clearly indicated and a full
and direct reference given to its author and place of valid publication, with
page or plate reference and date (but see Art. 33.2, 33.4, and 33.6).

Ex. 4.  In transferring Ectocarpus mucronatus D. A. Saunders to Giffordia, Kjeldsen &
Phinney (in Madroño 22: 90. 27 Apr 1973) cited the basionym and its author but without
reference to its place of valid publication. They later (in Madroño 22: 154. 2 Jul 1973)
validated the binomial G. mucronata (D. A. Saunders) Kjeldsen & Phinney by giving a full
and direct reference to the place of valid publication of the basionym.

Note 1.  For the purpose of this Code, a page reference (for publications with a
consecutive pagination) is a reference to the page or pages on which the ba-
sionym was validly published or on which the protologue is printed, but not to the
pagination of the whole publication unless it is coextensive with that of the pro-
tologue.

Ex. 5.  When proposing “Cylindrocladium infestans”, Peerally (in Mycotaxon 40: 337.
1991) cited the basionym as “Cylindrocladiella infestans Boesw., Can. J. Bot. 60: 2288-
2294. 1982”. As this refers to the pagination of Boeswinkel’s entire paper, not of the pro-
tologue of the intended basionym alone, the combination was not validly published by
Peerally.

33.4.  Errors in the citation of the basionym or replaced synonym, including
incorrect author citation (Art. 46), but not omissions (Art. 33.3; but
see Art. 33.2), do not invalidate publication of a new combination or no-
men novum
.

Ex. 6.  Aronia arbutifolia var. nigra (Willd.) F. Seym. (Fl. New England: 308. 1969) was
published as a new combination “Based on Mespilus arbutifolia L. var. nigra Willd., in Sp.
Pl. 2: 1013. 1800.” Willdenow treated these plants in the genus Pyrus, not Mespilus, and
publication was in 1799, not 1800; these errors are treated as bibliographic errors of cita-
tion and do not invalidate the publication of the new combination.

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33 Valid publication

33.5.  Mere reference to the Index kewensis, the Index of fungi, or any
work other than that in which the name was validly published does not
constitute a full and direct reference to the original publication of a name
(but see Art. 33.6) .

Ex. 7.  Ciferri (in Mycopathol. Mycol. Appl. 7: 86-89. 1954), in proposing 142 new com-
binations in Meliola, omitted references to places of publication of basionyms, stating that
they could be found in Petrak’s lists or in the Index of fungi; none of these combinations
was validly published. Similarly, Grummann (Cat. Lich. Germ.: 18. 1963) introduced a new
combination in the form Lecanora campestris f. “pseudistera (Nyl.) Grumm. c.n. – L. p.
Nyl., Z 5: 521”, in which “Z 5” referred to Zahlbruckner (Cat. Lich. Univ. 5: 521. 1928),
who gave the full citation of the basionym, Lecanora pseudistera Nyl.; Grummann’s com-
bination was not validly published.

Note 2.  The publication of a name for a taxon previously known under a misap-
plied name must be valid under Art. 32-45. This procedure is not the same as
publishing an avowed substitute (replacement name, nomen novum) for a validly
published but illegitimate name (Art. 58.1), the type of which is necessarily the
same as that of the name which it replaced (Art. 7.3).

Ex. 8.  Sadleria hillebrandii Rob. (1913) was introduced as a “nom. nov.” for “Sadleria
pallida
Hilleb. Fl. Haw. Is. 582. 1888. Not Hook. & Arn. Bot. Beech. 75. 1832.” Since the
requirements of Art. 32-45 were satisfied (for valid publication, prior to 1935, simple
reference to a previous description or diagnosis in any language was sufficient), the name
is validly published. It is, however, to be considered the name of a new species, validated
by Hillebrand’s description of the taxon to which he misapplied the name S. pallida Hook.
& Arn., and not a nomen novum as stated by Robinson; hence, Art. 7.3 does not apply.

Ex. 9.  Juncus bufonius “var. occidentalis” (Hermann in U.S. Forest Serv., Techn. Rep.
RM-18: 14. 1975) was published as a “nom. et stat. nov.” for J. sphaerocarpus “auct. Am.,
non Nees”. Since there is no Latin diagnosis, designation of type, or reference to any pre-
vious publication providing these requirements, the name is not validly published.

33.6.  In any of the following cases, reference to a work other than that in
which the basionym or replaced synonym was validly published is treated
as an error to be corrected, not affecting the valid publication of a new
combination or nomen novum, even if published on or after 1 January
1953:

(a)  when the name cited as basionym or replaced synonym was validly
      published earlier than in the cited publication, but in that cited publi-
      cation, in which all conditions for valid publication are again fulfilled,
      there is no reference to the actual place of valid publication;

(b)  when the failure to cite the place of valid publication of the basionym
      or replaced synonym is explained by the later nomenclatural starting
      point for the group concerned, and in particular by the backward shift
      of the starting date for some fungi;

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Valid publication 33

(c)  when an intended new combination would otherwise be validly pub-
      lished as a (legitimate or illegitimate) nomen novum; or

(d)  when an intended new combination or nomen novum would otherwise
      be the validly published name of a new taxon (see also Art. 33.2).

Ex. 10.  The combination Trichipteris kalbreyeri was proposed by Tryon (1970) with a full
and direct reference to Alsophila Kalbreyeri C. Chr. Ind. Fil. 44. 1905. This, however, is
not the place of valid publication of the intended basionym, which had previously been
published, with the same type, by Baker (1891; see Art. 6 Ex. 1). As Christensen provided
no reference to Baker’s earlier validation, Tryon’s error of citation does not affect the valid
publication of his
new combination, which is to be cited as T. kalbreyeri (Baker) R. M.
Tryon.

Ex. 11.  The intended new combination “Machaerina iridifolia” was proposed by Koyama
(in Bot. Mag. (Tokyo) 69: 64. 1956) with a full and direct reference to “Cladium iridifo-
lium
Baker, Flor. Maurit. 424 (1877)”. However, C. iridifolium had been proposed by
Baker as a new combination based on Scirpus iridifolius Bory (1804). As Baker provided
an explicit reference to Bory, Art. 33.6(a) does not apply and the combination under Ma-
chaerina
was not validly published by Koyama.

Ex. 12.  The combination Lasiobelonium corticale was proposed by Raitviir (1980) with a
full and direct reference to Peziza corticalis in Fries (Syst. Mycol. 2: 96. 1822). This,
however, is not the place of valid publication of the basionym, which, under the Code
operating in 1980, was in Mérat (Nouv. Fl. Env. Paris, ed. 2, 1: 22. 1821), and under the
current Code is in Persoon (Observ. Mycol. 1: 28. 1796). Raitviir’s error of citation, being
partly explained by the backward shift of the starting date for ascomycetes and partly by
the absence of a reference to Mérat in Fries’s work, does not invalidate the publication of
the new combination, which is to be cited as L. corticale (Pers. : Fr.) Raitv.

33.7.  A name given to a taxon of which the rank is at the same time, con-
trary to Art. 5, denoted by a misplaced term is not validly published. Such
misplacements include forms divided into varieties, species containing
genera, and genera containing families or tribes.

Ex. 13.  “Sectio Orontiaceae” was not validly published by Brown (Prodr.: 337. 1810)
since he misapplied the term “sectio” to a rank higher than genus.

Ex. 14.  “Tribus Involuta” and “tribus Brevipedunculata” (Huth in Bot. Jahrb. Syst. 20:
365, 368. 1895) are not validly published names, since Huth misapplied the term “tribus”
to a rank lower than section, within the genus Delphinium.

33.8.  An exception to Art. 33.7 is made for names of the subdivisions of
genera termed tribes (tribus) in Fries’s Systema mycologicum, which are
treated as validly published names of subdivisions of genera.

Ex. 15.  Agaricus “tribus” Pholiota Fr. (Syst. Mycol. 1: 240. 1821), sanctioned in the same
work, is the validly published basionym of the generic name Pholiota (Fr. : Fr.) P. Kumm.
(1871) (see Art. 32 Ex. 8).

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33A-34 Valid publication

Recommendation 33A

33A.1.  The full and direct reference to the place of publication of the basionym
or replaced synonym should immediately follow a proposed new combination or
nomen novum. It should not be provided by mere cross-reference to a bibliogra-
phy at the end of the publication or to other parts of the same publication, e.g. by
use of the abbreviations “loc. cit.” or “op. cit.”

Article 34

34.1.  A name is not validly published (a) when it is not accepted by the
author in the original publication; (b) when it is merely proposed in anti-
cipation of the future acceptance of the group concerned, or of a particular
circumscription, position, or rank of the group (so-called provisional
name), except as provided for in Art. 59; (c) when it is merely cited as a
synonym; (d) by the mere mention of the subordinate taxa included in the
taxon concerned. Art. 34.1(a) does not apply to names published with a
question mark or other indication of taxonomic doubt, yet accepted by
their author.

Ex. 1.  (a) “Sebertia”, proposed by Pierre (ms.) for a monotypic genus, was not validly
published by Baillon (in Bull. Mens. Soc. Linn. Paris 2: 945. 1891) because he did not
accept the genus. Although he gave a description of it, he referred its only species “Seber-
tia acuminata
Pierre (ms.)” to the genus Sersalisia R. Br. as S. ? acuminata, which he
thereby validly published under the provision of Art. 34.1, last sentence. The name Seber-
tia
was validly published by Engler (1897).

Ex. 2.  (a) The designations listed in the lefthand column of the Linnaean thesis Herbarium
amboinense
defended by Stickman (1754) were not names accepted by Linnaeus upon
publication and are not validly published.

Ex. 3.  (a) (b) The designation “Conophyton”, suggested by Haworth (Rev. Pl. Succ.: 82.
1821) for Mesembryanthemum sect. Minima Haw. (Rev. Pl. Succ.: 81. 1821) in the words
“If this section proves to be a genus, the name of Conophyton would be apt”, was not a
validly published generic name since Haworth did not adopt it or accept the genus. The
name was validly published as Conophytum N. E. Br. (1922).

Ex. 4.  (b) “Pteridospermaexylon” and “P. theresiae” were published by Greguss (in
Földt. Közl. 82: 171. 1952) for a genus and species of fossil wood. As Greguss explicitly
stated “Vorläufig benenne ich es mit den Namen ...” [provisionally I designate it by the
names ...], these are provisional names and as such are not validly published.

Ex. 5.  (c) “ Acosmus Desv.” was not validly published by Desfontaines (Cat. Pl. Hort.
Paris.: 233. 1829) when he cited it as a synonym of the generic name Aspicarpa Rich.

Ex. 6.  (c) “ Ornithogalum undulatum hort. Bouch.” was not validly published by Kunth,
(Enum. Pl. 4: 348. 1843) when he cited it as a synonym under Myogalum boucheanum
Kunth; the combination under Ornithogalum L. was validly published later: O. bouche-
anum
(Kunth) Asch. (1866).

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Valid publication 34

Ex. 7.  (d) The family designation “Rhaptopetalaceae” was not validly published by Pierre
(in Bull. Mens. Soc. Linn. Paris 2: 1296. Mai 1897), who merely mentioned the constituent
genera, Brazzeia Baill., “Scytopetalum”, and Rhaptopetalum Oliv., but gave no descrip-
tion or diagnosis; the family bears the name Scytopetalaceae Engl. (Oct 1897), accompa-
nied by a description.

Ex. 8.  (d) The generic designation “Ibidium” was not validly published by Salisbury (in
Trans. Hort. Soc. London 1: 291. 1812) who merely mentioned four included species but
supplied no generic description or diagnosis.

34.2.  When, on or after 1 January 1953, two or more different names
based on the same type are proposed simultaneously for the same taxon by
the same author (so-called alternative names), none of them is validly
published. This rule does not apply in those cases where the same combi-
nation is simultaneously used at different ranks, either for infraspecific
taxa within a species or for subdivisions of a genus within a genus (see
Rec. 22A.1 and 22A.2, 26A.1-3).

Ex. 9.  The species of Brosimum Sw. described by Ducke (in Arch. Jard. Bot. Rio de Ja-
neiro 3: 23-29. 1922) were published with alternative names under Piratinera Aubl. added
in a footnote (pp. 23-24). The publication of both sets of names, being effected before
1 January 1953, is valid.

Ex. 10.  “Euphorbia jaroslavii” (Poljakov in Bot. Mater. Gerb. Bot. Inst. Komarova Akad.
Nauk SSSR 15: 155. 1953) was published with an alternative designation, “Tithymalus ja-
roslavii”
. Neither was validly published. However, one name, Euphorbia yaroslavii (with
a different transliteration of the initial letter), was validly published by Poljakov (1961),
who effectively published it with a new reference to the earlier publication and simultane-
ously rejected the other name.

Ex. 11.  Description of “Malvastrum bicuspidatum subsp. tumidum S. R. Hill var. tumi-
dum,
subsp. et var. nov.” (in Brittonia 32: 474. 1980) simultaneously validated both M. bi-
cuspidatum
subsp. tumidum S. R. Hill and M. bicuspidatum var. tumidum S. R. Hill.

Ex. 12.  Hitchcock (in Univ. Wash. Publ. Biol. 17(1): 507-508. 1969) used the name Bro-
mus inermis
subsp. pumpellianus (Scribn.) Wagnon and provided a full and direct reference
to its basionym, B. pumpellianus Scribn. Within that subspecies, he recognized varieties,
one of which he named B. inermis var. pumpellianus (without author citation but clearly
based on the same basionym and type). In so doing, he met the requirements for valid
publication of B. inermis var. pumpellianus (Scribn.) C. L. Hitchc.

Note 1.  The name of a fungal holomorph and that of a correlated anamorph (see
Art. 59), even if validated simultaneously, are not alternative names in the sense
of Art. 34.2. They have different types, and the circumscription of the holomorph
is considered to include the anamorph, but not vice versa.

Ex. 13.  Lasiosphaeria elinorae Linder (1929), the name of a fungal holomorph, and the
simultaneously published name of a correlated anamorph, Helicosporium elinorae Linder,
are both valid, and both can be used under Art. 59.5 (see also Rec. 60C.2).

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34A-35 Valid publication

Recommendation 34A

34A.1.  Authors should avoid mentioning in their publications previously unpub-
lished names which they do not accept, especially if the persons responsible for these
unpublished names have not formally authorized their publication (see Rec. 23A.3(i)).

Article 35

35.1.  A new name or combination published on or after 1 January 1953
without a clear indication of the rank of the taxon concerned is not validly
published.

35.2.  For suprageneric names published on or after 1 January 1908, the
use of one of the terminations specified in Rec. 16A.1-3, Art. 17.1, 18.1,
19.1, and 19.3 is accepted as an indication of the corresponding rank, un-
less this (a) would conflict with the explicitly designated rank of the taxon
(which takes precedence) or (b) would result in a rank sequence contrary
to Art. 5 (in which case Art. 33.7 applies).

Ex. 1.  Jussieu (in Mém. Mus. Hist. Nat. 12: 497. 1827) proposed Zanthoxyleae without
specifying the rank. Although he employed the present termination for tribe (-eae), that
name, being published prior to 1908, is unranked. Zanthoxyleae Dumort. (Anal. Fam. Pl.:
45. 1829), however, is a tribal name, as Dumortier specified its rank.

Ex. 2.  Nakai (Chosakuronbun Mokuroku [Ord. Fam. Trib. Nov.], 1943) validly published
the names Parnassiales, Lophiolaceae, Ranzanioideae, and Urospatheae. He indicated the
respective ranks of order, family, subfamily, and tribe, by virtue of their terminations, even
though he did not mention these ranks explicitly.

35.3.  A new name or combination published before 1 January 1953 with-
out a clear indication of its rank is validly published provided that all
other requirements for valid publication are fulfilled; it is, however, inop-
erative in questions of priority except for homonymy (see Art. 53.4). If it
is a new name, it may serve as a basionym for subsequent combinations or
a replaced synonym for nomina nova in definite ranks.

Ex. 3.  The groups “Soldanellae”, “Sepincoli”, “Occidentales”, etc., were published with-
out any indication of rank under Convolvulus L. by House (in Muhlenbergia 4: 50. 1908).
The names C. [unranked] Soldanellae, etc., are validly published but they are not in any defi-
nite rank and have no status in questions of priority except that they may act as homonyms.

Ex. 4.  In Carex L., the epithet Scirpinae was used in the name of an infrageneric taxon of
no stated rank by Tuckerman (Enum. Meth. Caric.: 8. 1843); this taxon was assigned
sectional rank by Kükenthal (in Engler, Pflanzenr. 38: 81. 1909) and its name may be cited
as Carex sect. Scirpinae (Tuck.) Kük. (C. [unranked] Scirpinae Tuck.).

35.4.  If in one whole publication (Art. 35.5), prior to 1 January 1890, only
one infraspecific rank is admitted, it is considered to be that of variety un-
less this would be contrary to the author’s statements in the same publication.

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Valid publication 35-36A

35.5.  In questions of indication of rank, all publications appearing under
the same title and by the same author, such as different parts of a flora
issued at different times (but not different editions of the same work),
must be considered as a whole, and any statement made therein designat-
ing the rank of taxa included in the work must be considered as if it had
been published together with the first instalment.

Article 36

36.1.  On or after 1 January 1935 a name of a new taxon (algal and all
fossil taxa excepted) must, in order to be validly published, be accompa-
nied by a Latin description or diagnosis or by a reference to a previously
and effectively published Latin description or diagnosis (but see Art. H.9).

Ex. 1.  Arabis “Sekt. Brassicoturritis O. E. Schulz” and “Sekt. Brassicarabis O. E. Schulz”
(in Engler & Prantl, Nat. Pflanzenfam., ed. 2, 17b: 543-544. 1936), published with German
but no Latin descriptions or diagnoses, are not validly published names.

Ex. 2.  “Schiedea gregoriana” (Degener, Fl. Hawaiiensis, fam. 119. 9 Apr 1936) was ac-
companied by an English but no Latin description and is accordingly not a validly pub-
lished name. S. kealiae Caum & Hosaka (in Occas. Pap. Bernice Pauahi Bishop Mus.
11(23): 3. 10 Apr 1936), the type of which is part of the material used by Degener, is
provided with a Latin description and is validly published.

Ex. 3.  Alyssum flahaultianum Emb., first published without a Latin description or diagno-
sis (in Bull. Soc. Hist. Nat. Maroc 15: 199. 1936), was validly published posthumously
when a Latin translation of Emberger’s original French description was provided (in Will-
denowia 15: 62-63. 1985).

36.2.  In order to be validly published, a name of a new taxon of non-
fossil algae published on or after 1 January 1958 must be accompanied by
a Latin description or diagnosis or by a reference to a previously and ef-
fectively published Latin description or diagnosis.

Ex. 4.  Although Neoptilota Kylin (Gatt. Rhodophyc.: 392. 1956) was accompanied by
only a German description, it is a validly published name since it applies to an alga and
was published before 1958.

36.3.  In order to be validly published, a name of a new taxon of fossil
plants published on or after 1 January 1996 must be accompanied by a
Latin or English description or diagnosis or by a reference to a previously
and effectively published Latin or English description or diagnosis.

Recommendation 36A

36A.1.  Authors publishing names of new taxa of non-fossil plants should give or
cite a full description in Latin in addition to the diagnosis.

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37 Valid publication

Article 37

37.1.  Publication on or after 1 January 1958 of the name of a new taxon of
the rank of genus or below is valid only when the type of the name is indi-
cated (see Art. 7-10; but see Art. H.9 Note 1 for the names of certain hybrids).

37.2.  For the name of a new species or infraspecific taxon, indication of
the type
as required by Art. 37.1 can be achieved by reference to an entire
gathering, or part thereof, even if it consists of two or more
specimens as
defined in Art.
8 (see also Art. 37.5).

Ex. 1.  The protologue of Laurentia frontidentata E. Wimm. (in Engler, Pflanzenr. 108:
855. 1968) includes the type statement “E. Esterhuysen No. 17070! Typus - Pret., Bol.”
The name is validly published because a single gathering is cited, despite the mention of
duplicate specimens in two different herbaria.

37.3.  For the name of a new genus or subdivision of a genus, reference
(direct or indirect) to one species name only, or the citation of the holo-
type or lectotype of one previously or simultaneously published species
name only, even if that element is not explicitly designated as type, is
acceptable as
indication of the type (see also Art. 22.6; but see Art. 37.5).
Similarly, for the name of a new species or infraspecific taxon, mention of
a single specimen or gathering (Art. 37.2) or illustration (when permitted
by Art. 37.4), even if that
element is not explicitly designated as type, is
acceptable as indication of the type (but see Art. 37.5).

Ex. 2.  “Baloghia pininsularis” was published by Guillaumin (in Mém. Mus. Natl. Hist. Nat.,
B, Bot. 8: 260. 1962) with two cited gatherings: Baumann 13813 and Baumann 13823. As
the author failed to designate one of them as the type, he did not validly publish the name.
Valid publication was effected in McPherson & Tirel (in Fl. Nouv.-Caléd. 14: 58. 1987), who
wrote “Lectotype (désigné ici): Baumann-Bodenheim 13823 (P!; iso-, Z)” while providing
a full and direct reference to Guillaumin’s Latin description (Art. 45.1; see Art. 46 Ex. 8).

Note 1.  Mere citation of a locality does not constitute mention of a single speci-
men or gathering.
Concrete reference to some detail relating to the actual type,
such as the
collector’s name or collecting number or date, is required.

37.4.  For the purpose of this Article, the type of a name of a new species
or infraspecific taxon (fossils excepted: see Art. 8.5) may be an illustra-
tion if, and only if, it is impossible to preserve a specimen.

Note 2.  Cultures of fungi and algae preserved in a metabolically inactive state are
acceptable as types (Art. 8.4; see also Rec. 8B.1).

37.5.  For the name of a new taxon of the rank of genus or below pub-
lished on or after 1 January 1990, indication of the type must include one
of the words “typus” or “holotypus”, or its abbreviation, or its equivalent
in a modern language (see also Rec. 37A and Art. 38.2).

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Valid publication 37-39A

37.6.  For the name of a new species or infraspecific taxon published on or
after 1 January 1990 of which the type is a specimen or unpublished il-
lustration, the single herbarium or collection or institution in which the
type is conserved must be specified.

Note 3.  Specification of the herbarium or collection or institution may be made in
an abbreviated form, e.g. as given in Index herbariorum, part I, or in the World
directory of collections of cultures of microorganisms
.

Recommendation 37A

37A.1.  The indication of the nomenclatural type should immediately follow the
description or diagnosis and should include the Latin word “typus” or “holoty-
pus”.

Article 38

38.1.  In order to be validly published, a name of a new taxon of fossil
plants of specific or lower rank published on or after 1 January 1912 must
be accompanied by an illustration or figure showing the essential charac-
ters, in addition to the description or diagnosis, or by a reference to a pre-
viously and effectively published illustration or figure.

38.2.  For the name of a new species or infraspecific taxon of fossil plants
published on or after 1 January 2001, one of the validating illustrations
must be identified as representing the type specimen (see also Art. 9.13
and 37.5).

Article 39

39.1.  In order to be validly published, a name of a new taxon of non-fossil
algae of specific or lower rank published on or after 1 January 1958 must be
accompanied by an illustration or figure showing the distinctive morpho-
logical features, in addition to the Latin description or diagnosis, or by a
reference to a previously and effectively published illustration or figure.

Recommendation 39A

39A.1.  The illustration or figure required by Art. 39 should be prepared from
actual specimens, preferably including the holotype.

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40-41 Valid publication

Article 40

40.1.  In order to be validly published, names of hybrids of specific or
lower rank with Latin epithets must comply with the same rules as names
of non-hybrid taxa of the same rank.

Ex. 1.  “Nepeta ×faassenii” (Bergmans, Vaste Pl. Rotsheesters, ed. 2: 544. 1939, with a
description in Dutch; Lawrence in Gentes Herb. 8: 64. 1949, with a diagnosis in English)
is not validly published, not being accompanied by or associated with a Latin description
or diagnosis. The name Nepeta ×faassenii Bergmans ex Stearn (1950) is validly published,
being accompanied by a Latin description.

Ex. 2.  “Rheum ×cultorum” (Thorsrud & Reisaeter, Norske Plantenavn: 95. 1948), being
there a nomen nudum, is not validly published.

Ex. 3.  “Fumaria ×salmonii” (Druce, List Brit. Pl.: 4. 1908) is not validly published, as
only the presumed parentage F. densiflora × F. officinalis is stated.

Note 1.  For names of hybrids of the rank of genus or subdivision of a genus, see
Art. H.9.

Article 41

41.1.  In order to be validly published, a name of a family or subdivision
of a family must be accompanied (a) by a description or diagnosis of the
taxon, or (b) by a reference (direct or indirect) to a previously and effec-
tively published description or diagnosis of a family or subdivision of a
family.

Ex. 1.  “ Pseudoditrichaceae fam. nov.” (Steere & Iwatsuki in Canad. J. Bot. 52: 701. 1974)
was not a validly published name of a family as there was no Latin description or diagno-
sis nor reference to either, but only mention of the single included genus and species (see
Art. 34.1(d)), “Pseudoditrichum mirabile gen. et sp. nov.”, for both of which the name was
validated under Art. 42 by a single Latin diagnosis.

41.2.  In order to be validly published, a name of a genus or subdivision of
a genus must be accompanied (a) by a description or diagnosis of the
taxon (but see Art. 42), or (b) by a reference (direct or indirect) to a previ-
ously and effectively published description or diagnosis of a genus or
subdivision of a genus.

Ex. 2.  Validly published generic names: Carphalea Juss., accompanied by a generic de-
scription; Thuspeinanta T. Durand, replacing the name of the previously described genus
Tapeinanthus Boiss. ex Benth. (non Herb.); Aspalathoides (DC.) K. Koch, based on the name
of a previously described section, Anthyllis sect. Aspalathoides DC.; Scirpoides Ség. (Pl. Ve-
ron. Suppl.: 73. 1754), accepted there but without a generic description or diagnosis, vali-
dated by indirect reference (through the title of the book and a general statement in the pref-
ace) to the generic diagnosis and further direct references in Séguier (Pl. Veron. 1: 117. 1745).

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Valid publication 41-42

Note 1.  An exception to Art. 41.2 is made for the generic names first published
by Linnaeus in Species plantarum, ed. 1 (1753) and ed. 2 (1762-1763), which are
treated as having been validly published on those dates (see Art. 13.4).

Note 2.  In certain circumstances, an illustration with analysis is accepted as
equivalent to a generic description or diagnosis (see Art. 42.3).

41.3.  In order to be validly published, a name of a species or infraspecific
taxon must be accompanied (a) by a description or diagnosis of the taxon
(but see Art. 42 and 44), or (b) by a reference to a previously and effec-
tively published description or diagnosis of a species or infraspecific taxon.
A name of a species may also be validly published (c), under certain cir-
cumstances, by reference to a genus the name of which was previously
and validly published simultaneously with its description or diagnosis. A
reference as mentioned under (c) is acceptable only if neither the author of
the name of the genus nor the author of the name of the species indicate
that more than one species belongs to the genus in question.

Ex. 3.  Trilepisium Thouars (1806) was validated by a generic description but without
mention of a name of a species. T. madagascariense DC. (1828) was subsequently pro-
posed without a description or diagnosis of the species. Neither author gave any indication
that there was more than one species in the genus. Candolle’s specific name is therefore
validly published.

Article 42

42.1.  The names of a genus and a species may be simultaneously vali-
dated by provision of a single description (descriptio generico-specifica)
or diagnosis, even though this may have been intended as only generic or
specific, if all of the following conditions obtain: (a) the genus is at that
time monotypic; (b) no other names (at any rank) have previously been
validly published based on the same type; and (c) the names of the genus
and species otherwise fulfil the requirements for valid publication. Refer-
ence to an earlier description or diagnosis is not acceptable in place of a
descriptio generico-specifica.

42.2.  For the purpose of Art. 42, a monotypic genus is one for which a
single binomial is validly published, even though the author may indicate
that other species are attributable to the genus.

Ex. 1.  Nylander (1879) described the new species “Anema nummulariellum” in a new
genus “Anema” without providing a generic description or diagnosis. Since at the same time
he also transferred Omphalaria nummularia Durieu & Mont. to “Anema”, none of his names
was validly published. They were later validated by Forsell (1885).

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42-43 Valid publication

Ex. 2.  The names Kedarnatha P. K. Mukh. & Constance (1986) and K. sanctuarii P. K.
Mukh. & Constance, the latter designating the single, new species of the new genus, are both
validly published although a Latin description was provided only under the generic name.

Ex. 3.  Piptolepis phillyreoides Benth. (1840) was a new species assigned to the monotypic
new genus Piptolepis published with a combined generic and specific description, and both
names are validly published.

Ex. 4.  In publishing “Phaelypea” without a generic description or diagnosis, P. Browne
(Civ. Nat. Hist. Jamaica: 269. 1756) included and described a single species, but he gave
the species a phrase-name not a validly published binomial. Art. 42 does not therefore ap-
ply and “Phaelypea” is not a validly published name.

42.3.  Prior to 1 January 1908 an illustration with analysis, or for non-vascu-
lar plants a single figure showing details aiding identification, is acceptable,
for the purpose of this Article, in place of a written description or diagnosis.

42.4.  For the purpose of Art. 42, an analysis is a figure or group of fig-
ures, commonly separate from the main illustration of the plant (though
usually on the same page or plate), showing details aiding identification,
with or without a separate caption.

Ex. 5.  The generic name Philgamia Baill. (1894) was validly published, as it appeared on
a plate with analysis of the only included species, P. hibbertioides Baill., and was pub-
lished before 1 January 1908.

Article 43

43.1.  A name of a taxon below the rank of genus is not validly published
unless the name of the genus or species to which it is assigned is validly
published at the same time or was validly published previously.

Ex. 1.  Binary designations for six species of “Suaeda”, including “S. baccata” and “S.
vera”,
were published with descriptions and diagnoses by Forsskål (Fl. Aegypt.-Arab.: 69-
71. 1775), but he provided no description or diagnosis for the genus: these were not there-
fore validly published names.

Ex. 2.  Müller (in Flora 63: 286. 1880) published the new genus “Phlyctidia” with the
species “P. hampeana n. sp.”, “P. boliviensis” (= Phlyctis boliviensis Nyl.), “P. sorediifor-
mis”
(= Phlyctis sorediiformis Kremp.), “P. brasiliensis” (= Phlyctis brasiliensis Nyl.), and
“P. andensis” (= Phlyctis andensis Nyl.). These were not, however, validly published
specific names in this place, because the intended generic name “Phlyctidia” was not
validly published; Müller gave no generic description or diagnosis but only a description and a
diagnosis of the new species “P. hampeana”. This description and diagnosis did not validate
the generic name as a descriptio generico-specifica under Art. 42 since the new genus was not
monotypic. Valid publication of the name Phlyctidia was by Müller (1895), who provided a
short generic diagnosis and explicitly included only two species, P. ludoviciensis Müll. Arg.
and P. boliviensis (Nyl.) Müll. Arg. The latter names were also validly published in 1895.

Note 1.  This Article applies also when specific and other epithets are published
under words not to be regarded as generic names (see Art. 20.4).

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Valid publication 43-45

Ex. 3.  The binary designation “Anonymos aquatica” (Walter, Fl. Carol.: 230. 1788) is not
a validly published name. The correct name for the species concerned is Planera aquatica
J. F. Gmel. (1791), and the date of the name, for purposes of priority, is 1791. The name
must not be cited as “P. aquatica (Walter) J. F. Gmel.”

Ex. 4.  Despite the existence of the generic name Scirpoides Ség. (1754), the binary desig-
nation “S. paradoxus” (Rottbøll, Descr. Pl. Rar.: 27. 1772) is not validly published since
“Scirpoides” in Rottbøll’s context was a word not intended as a generic name. The first
validly published name for this species is Fuirena umbellata Rottb. (1773).

Article 44

44.1.  The name of a species or of an infraspecific taxon published before
1 January 1908 may be validly published even if only accompanied by an
illustration with analysis (as defined in Art. 42.4).

Ex. 1.  Panax nossibiensis Drake (1896) was validly published on a plate with analysis.

44.2.  Single figures of non-vascular plants showing details aiding identifi-
cation are considered as illustrations with analysis (see also Art. 42.4).

Ex. 2.  Eunotia gibbosa Grunow (1881), a name of a diatom, was validly published by pro-
vision of a figure of a single valve.

Article 45

45.1.  The date of a name is that of its valid publication. When the various
conditions for valid publication are not simultaneously fulfilled, the date
is that on which the last is fulfilled. However, the name must always be
explicitly accepted in the place of its validation. A name published on or
after 1 January 1973 for which the various conditions for valid publication
are not simultaneously fulfilled is not validly published unless a full and
direct reference (Art. 33.3) is given to the places where these requirements
were previously fulfilled.

Ex. 1.  “Clypeola minor” first appeared in the Linnaean thesis Flora monspeliensis (1756),
in a list of names preceded by numerals but without an explanation of the meaning of these
numerals and without any other descriptive matter; when the thesis was reprinted in vol. 4
of the Amoenitates academicae (1759), a statement was added explaining that the numbers
referred to earlier descriptions published in Magnol’s Botanicon monspeliense. However,
“Clypeola minor” was absent from the reprint, being no longer accepted by Linnaeus, and
was not therefore validly published.

Ex. 2.  When proposing “Graphis meridionalis” as a new species, Nakanishi (in J. Sci.
Hiroshima Univ., Ser. B(2), 11: 75. 1966) provided a Latin description but failed to desig-
nate a holotype. G. meridionalis M. Nakan. was validly published in 1967 (in J. Sci. Hi-
roshima Univ., Ser. B(2), 11: 265) when he designated the holotype of the name and pro-
vided a full and direct reference to the previous publication.

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45-45A Valid publication

45.2.  A correction of the original spelling of a name (see Art. 32.5 and 60)
does not affect its date of valid publication.

Ex. 3.  The correction of the erroneous spelling of Gluta “benghas” (Linnaeus, Mant.: 293.
1771) to G. renghas L. does not affect the date of publication of the name even though the
correction dates only from 1883 (Engler in Candolle & Candolle, Monogr. Phan. 4: 225).

45.3.  For purposes of priority only legitimate names are taken into con-
sideration (see Art. 11, 52-54). However, validly published earlier homo-
nyms, whether legitimate or not, shall cause rejection of their later homo-
nyms, unless the latter are conserved or sanctioned (but see Art. 15 Note 1).

45.4.  If a taxon originally assigned to a group not covered by this Code is
treated as belonging to a group of plants other than algae, the authorship
and date of any of its names are determined by the first publication that
satisfies the requirements for valid publication under this Code. If the
taxon is treated as belonging to the algae, any of its names need satisfy
only the requirements of the pertinent non-botanical Code for status
equivalent to valid publication under the present Code (but see Art. 54,
regarding homonymy).

Ex. 4.  Amphiprora Ehrenb. (1843) is an available¹ name for a genus of animals first
treated as belonging to the algae by Kützing (1844). Amphiprora has priority in botanical
nomenclature from 1843, not 1844.

Ex. 5.  Petalodinium Cachon & Cachon-Enj. (in Protistologia 5: 16. 1969) is available under
the International code of zoological nomenclature as the name of a genus of dinoflagel-
lates. When the taxon is treated as belonging to the algae, its name retains its original author-
ship and date even though the original publication lacked a Latin description or diagnosis.

Ex. 6.  Labyrinthodyction Valkanov (in Progr. Protozool. 3: 373. 1969), although available
under the International code of zoological nomenclature as the name of a genus of rhizo-
pods, is not valid when the taxon is treated as belonging to the fungi because the original
publication lacked a Latin description or diagnosis.

Ex. 7.  Protodiniferaceae Kof. & Swezy (in Mem. Univ. Calif. 5: 111. 1921, “Protodinife-
ridae”
), available under the International code of zoological nomenclature, is validly
published as a name of a family of algae with its original authorship and date but with the
original termination changed in accordance with Art. 18.4 and 32.5.

Recommendation 45A

45A.1.  Authors using new names in works (floras, catalogues, etc.) written in a
modern language should simultaneously comply with the requirements of valid
publication.

———————————————————————

¹The word “available” in the International code of zoological nomenclature is equivalent to
  “validly published” in the present Code.

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Valid publication – Author citations 45B-46

Recommendation 45B

45B.1.  Authors should indicate precisely the dates of publication of their works.
In a work appearing in parts the last-published sheet of the volume should indi&
cate the precise dates on which the different fascicles or parts of the volume were
published as well as the number of pages and plates in each.

Recommendation 45C

45C.1.  On separately printed and issued copies of works published in a periodi-
cal, the name of the periodical, the number of its volume or parts, the original
pagination, and the date (year, month, and day) should be indicated.

SECTION 3AUTHOR CITATIONS

Article 46

46.1.  In publications, particularly those dealing with taxonomy and no-
menclature, it may be desirable, even when no bibliographic reference to
the protologue is made, to cite the author(s) of the name concerned (see Art.
6
Note 1; see also Art. 22.1 and 26.1). In so doing, the following rules are to
be followed.

46.2.  A name of a new taxon must be attributed to the author or authors to
whom both the name and the validating description or diagnosis were
ascribed, even when authorship of the publication is different. A new
combination or a nomen novum must be attributed to the author or authors
to whom it was ascribed when, in the publication in which it appears, it is
explicitly stated that they contributed in some way to that publication. Art.
46.4 notwithstanding, authorship of a new name or combination must
always be accepted as ascribed, even when it differs from authorship of
the publication, when at least one author is common to both.

Ex. 1.  Rosaceae Adans., Rosa L., Rosa gallica L., Rosa gallica var. eriostyla R. Keller,
Rosa gallica L. var. gallica.

Ex. 2.  The name Viburnum ternatum was published in Sargent (Trees & Shrubs 2: 37.
1907). It was ascribed to “Rehd.”, and the whole account of the species was signed “Alfred
Rehder” at the end of the article. The name is therefore cited as V. ternatum Rehder.

Ex. 3.  In a paper by Hilliard & Burtt (1986) names of new species of Schoenoxiphium,
including S. altum, were ascribed to Kukkonen, preceded by a statement “The following
diagnostic descriptions of new species have been supplied by Dr. I. Kukkonen in order to
make the names available for use”. The name is therefore cited as S. altum Kukkonen.

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46 Author citations

Ex. 4.  In Torrey & Gray (1838) the names Calyptridium and C. monandrum were ascribed
to “Nutt. mss.”, and the descriptions were enclosed in double quotes indicating that Nuttall
wrote them, as acknowledged in the preface. The names are therefore cited as Calyptridium
Nutt. and C. monandrum Nutt.

Ex. 5.  The name Brachystelma was published by Sims (1822) who by implication ascribed
it to Brown and added “Brown, Mscr.” at the end of the generic diagnosis, indicating that
Brown wrote it. The name is therefore cited as Brachystelma R. Br.

Ex. 6.  Green (1985) ascribed the new combination Neotysonia phyllostegia to Paul
G. Wilson and elsewhere in the same publication acknowledged his assistance. The name
is therefore cited as N. phyllostegia (F. Muell.) Paul G. Wilson.

Ex. 7.  The authorship of Steyerbromelia discolor L. B. Sm. & H. Rob. (1984) is accepted
as originally ascribed, although the new species was described in a paper authored by
Smith alone. The same applies to the new combination Sophora tomentosa subsp. occi-
dentalis
(L.) Brummitt (in Kirkia 5: 265. 1966), thus ascribed, published in a paper
authored jointly by Brummitt & Gillett.

Ex. 8.  The appropriate author citation for Baloghia pininsularis (see Art. 37 Ex. 2) is
Guillaumin, and not McPherson & Tirel, because both the name and validating description
were ascribed to Guillaumin in the protologue.

Note 1.  When authorship of a name differs from authorship of the publication in
which it was validly published, both are sometimes cited, connected by the word
“in”. In such a case, “in” and what follows are part of a bibliographic citation and
are better omitted unless the place of publication is being cited.

Ex. 9.  The original description of the new species Verrucaria aethiobola Wahlenb. (in
Acharius, Methodus, Suppl.: 17. 1803) is ascribed by Acharius to “Wahlenb. Msc.”, and
the name itself is ascribed to “Wahlenb.” (not in the text of the Supplement but in the
index to the Methodus, p. 392). The name is therefore appropriately cited as V. aethiobola
Wahlenb., better not as V. aethiobola “Wahlenb. in Acharius” (unless followed by a bib-
liographic citation of the place of publication), and certainly not as V. aethiobola “Wah-
lenb. ex Ach.”

46.3.  For the purposes of this Article, ascription is the direct association
of the name of a person or persons with a new name or description or
diagnosis of a taxon. An author citation appearing in a list of synonyms
does not constitute ascription, nor does reference to a basionym or a re-
placed synonym, including bibliographic errors, or reference to a homo-
nym, or a formal error.

Ex. 10.  Hypnum crassinervium Wilson (1833) was not ascribed to Taylor by Wilson’s
citing “Hypnum crassinervium Dr. Taylor’s MS” in the list of synonyms.

Ex. 11.  Lichen debilis Sm. (1812) was not ascribed to Turner and Borrer by Smith’s citing
Calicium debile Turn. and Borr. Mss.” as a synonym.

Ex. 12.  When Opiz (1852) wrote “Hemisphace Bentham” he did not ascribe the generic
name to Bentham but provided an indirect reference to the basionym, Salvia sect. Hemi-
sphace
Benth. (see Art. 32 Ex. 5).

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Author citations 46

Ex. 13.  When Brotherus (1907) published “Dichelodontium nitidulum Hooker & Wilson”
he provided an indirect reference to the basionym, Leucodon nitidulus Hook. f. & Wilson,
and did not ascribe the new combination to Hooker and Wilson. He did, however, ascribe
to them the simultaneously published name of his new genus, Dichelodontium.

Ex. 14.  When Sirodot (1872) wrote “Lemanea Bory” he in fact published a later homonym
(see Art. 48 Ex. 1). His reference to Bory is not therefore ascription of the later homonym,
Lemanea Sirodot, to Bory.

46.4.  A name of a new taxon must be attributed to the author or authors
of the publication in which it appears when only the name but not the
validating description or diagnosis was ascribed to a different author or
different authors. A new combination or a nomen novum must be attrib-
uted to the author or authors of the publication in which it appears, al-
though it was ascribed to a different author or to different authors, when
no separate statement was made that they contributed in some way to that
publication. However, in both cases authorship as ascribed, followed by
“ex”, may be inserted before the name(s) of the publishing author(s).

Ex. 15.  Seemann (1865) published Gossypium tomentosum “Nutt. mss.”, followed by a
validating description not ascribed to Nuttall; the name may be cited as G. tomentosum
Nutt. ex Seem. or G. tomentosum Seem.

Ex. 16.  The name Lithocarpus polystachyus published by Rehder (1919) was based on
Quercus polystachya A. DC. (1864), ascribed by Candolle to “Wall.! list n. 2789” but
formerly a nomen nudum; Rehder’s combination may be cited as L. polystachyus (Wall. ex
A. DC.) Rehder or L. polystachyus (A. DC.) Rehder.

Ex. 17.  Lilium tianschanicum was described by Grubov (1977) as a new species and its
name was ascribed to Ivanova; since there is no indication that Ivanova provided the vali-
dating description, the name may be cited as L. tianschanicum N. A. Ivanova ex Grubov or
L. tianschanicum Grubov.

Ex. 18.  In a paper by Boufford, Tsi and Wang (1990) the name Rubus fanjingshanensis
was ascribed to Lu with no indication that Lu provided the description; the name should be
attributed to Boufford & al. or to L. T. Lu ex Boufford & al.

Ex. 19.  Green (1985) ascribed the new combination Tersonia cyathiflora to “(Fenzl) A.
S. George”; since Green nowhere mentioned that George had contributed in any way, the
combining author must be cited as A. S. George ex J. W. Green or just J. W. Green.

Ex. 20.  However, R. Brown is accepted as the author of the treatments of genera and
species appearing under his name in Aiton’s Hortus kewensis, ed. 2 (1810-1813), even
when new names or the descriptions validating them are not explicitly ascribed to him. In a
postscript to that work (op. cit. 5: 532. 1813), Aiton wrote: “Much new matter has been
added by [Robert Brown] ... the greater part of his able improvements are distinguished by
the signature Brown mss.” The latter phrase is therefore a statement of authorship not
merely an ascription. For example, the combination Oncidium triquetrum, based by indi-
rect reference on Epidendrum triquetrum Sw. (1788), is to be cited as O. triquetrum (Sw.)
R. Br. (1813) and not attributed to “R. Br. ex Aiton”, or to Aiton alone, because in the
generic heading Brown is credited with authorship of the treatment of Oncidium.

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46 Author citations

46.5.  The citation of an author who published the name before the start-
ing point of the group concerned may be indicated by the use of the word
“ex”. For groups with a starting point later than 1753, when a pre-starting
point name was changed in rank or taxonomic position by the first author
who validly published it, the name of the pre-starting point author may be
added in parentheses, followed by “ex”.

Ex. 21.  Linnaeus (1754) ascribed the name Lupinus to the pre-starting-point author Tour-
nefort; the name may be cited as Lupinus Tourn. ex L. (1753) or Lupinus L. (see Art. 13.4).

Ex. 22.  Lyngbya glutinosa C. Agardh (Syst. Alg.: 73. 1824) was taken up by Gomont in
the publication which marks the starting point of the “Nostocaceae heterocysteae” (in
Ann. Sci. Nat., Bot., ser. 7, 15: 339. 1892) as Hydrocoleum glutinosum. This may be cited
as H. glutinosum (C. Agardh) ex Gomont.

46.6.  In determining the correct author citation, only internal evidence in
the publication (as defined in Art. 35.5) where the name was validly pub-
lished is to be accepted, including ascription of the name, statements in
the introduction, title, or acknowledgements, and typographical or stylistic
distinctions in the text.

Ex. 23.  Names first published in Britton & Brown’s Illustrated flora of the northern
United States
(1896-1898; ed. 2, 1913) must, unless ascribed to Britton alone (see Art.
46.2), be attributed to “Britton & A. Br.”, since the title page attributes the whole work to
both, even though it is generally accepted that A. Brown did not participate in writing it.

Ex. 24.  Although the descriptions in Aiton’s Hortus kewensis (1789) are generally consid-
ered to have been written by Solander or Dryander, the names of new taxa published there
must be attributed to Aiton, the stated author of the work, except where a name and de-
scription were both ascribed in that work to somebody else.

Ex. 25.  The name Andreaea angustata was published in a work of Limpricht (1885) with
the ascription “nov. sp. Lindb. in litt. ad Breidler 1884”, but there is no internal evidence
that Lindberg had supplied the validating description. Authorship is therefore to be cited as
“Limpr.” or “Lindb. ex Limpr.”

Note 2.  External evidence may be used to determine authorship of new names
and combinations included in a publication or article for which there is no inter-
nal evidence of authorship.

Ex. 26.  No authorship appears anywhere in the work known as “Cat. Pl. Upper Louisiana.
1813”, a catalogue of plants available from the Fraser Brothers Nursery. Based on external
evidence (cf. Stafleu & Cowan in Regnum Veg. 105: 785. 1981), authorship of the docu-
ment, and of new names such as Oenothera macrocarpa that are published in it, are attrib-
uted to Thomas Nuttall.

Ex. 27.  The book that appeared under the title Vollständiges systematisches Verzeichniß
aller Gewächse Teutschlandes
... (Leipzig 1782) bears no explicit authorship but is attrib-
uted to “einem Mitgliede der Gesellschaft Naturforschender Freunde”. External evidence
may be used to determine that G. A. Honckeny is the author of the work and of new names
that appear in it (e.g. Poa vallesiana Honck., Phleum hirsutum Honck.; but see Art. 23 Ex.
14), as done by Pritzel (Thes. Lit. Bot.: 123. 1847).

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Author citations 46-46B

Note 3.  Authors publishing new names and wishing to establish that other persons’
names followed by “ex” may precede theirs in authorship citation may adopt the
“ex” citation in the protologue.

Ex. 28.  In validating the name Nothotsuga, Page (1989) cited it as “Nothotsuga H.-H. Hu
ex C. N. Page”, noting that in 1951 Hu had published it as a nomen nudum; the name may
be attributed to Hu ex C. N. Page or just C. N. Page.

Ex. 29.  Atwood (1981) ascribed the name of a new species, Maxillaria mombachoënsis, to
“Heller ex Atwood”, with a note stating that it was originally named by Heller, then de-
ceased; the name may be attributed to A. H. Heller ex J. T. Atwood or just J. T. Atwood.

Recommendation 46A

46A.1.  For the purpose of author citation, prefixes indicating ennoblement (see Rec.
60C.4(d-e)) should be suppressed unless they are an inseparable part of the name.

Ex. 1.  Lam. for J. B. P. A. Monet Chevalier de Lamarck, but De Wild. for E. De Wilde-
man.

46A.2.  When a name in an author citation is abbreviated, the abbreviation should
be long enough to be distinctive, and should normally end with a consonant that,
in the full name, precedes a vowel. The first letters should be given without any
omission
, but one of the last characteristic consonants of the name may be added
when this is customary.

Ex. 2.  L. for Linnaeus; Fr. for Fries; Juss. for Jussieu; Rich. for Richard; Bertol. for Ber-
toloni, to distinguish it from Bertero; Michx. for Michaux, to distinguish it from Micheli.

46A.3.  Given names or accessory designations serving to distinguish two bota-
nists of the same name should be abridged in the same way.

Ex. 3.  R. Br. for Robert Brown; A. Juss. for Adrien de Jussieu; Burm. f. for Burman filius;
J. F. Gmel. for Johann Friedrich Gmelin, J. G. Gmel. for Johann Georg Gmelin, C.
C. Gmel. for Carl Christian Gmelin, S. G. Gmel. for Samuel Gottlieb Gmelin; Müll. Arg.
for Jean Müller argoviensis (of Aargau).

46A.4.  When it is a well-established custom to abridge a name in another man-
ner, it is advisable to conform to custom.

Ex. 4.  DC. for Augustin-Pyramus de Candolle; St.-Hil. for Saint-Hilaire.

Note 1.  Brummitt & Powell’s Authors of plant names (1992) provides unambi-
guous standard abbreviations, in conformity with the present Recommendation,
for a large number of authors of plant names, and these abbreviations have been
used for author citations throughout the present Code.

Recommendation 46B

46B.1.  In citing the author of the scientific name of a taxon, the romanization of
the author’s name given in the original publication should normally be accepted.
Where an author failed to give a romanization, or where an author has at different

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Author citations 46B-47

times used different romanizations, then the romanization known to be preferred
by the author or that most frequently adopted by the author should be accepted. In
the absence of such information the author’s name should be romanized in accor-
dance with an internationally available standard.

46B.2.  Authors of scientific names whose personal names are not written in Ro-
man letters should romanize their names, preferably (but not necessarily) in ac-
cordance with an internationally available standard and, as a matter of typo-
graphical convenience, without diacritical signs. Once authors have selected the
romanization of their personal names, they should use it consistently thereafter.
Whenever possible, authors should not permit editors or publishers to change the
romanization of their personal names.

Recommendation 46C

46C.1.  After a name published jointly by two authors, both authors should be
cited, linked by the word “et” or by an ampersand (&).

Ex. 1.  Didymopanax gleasonii Britton et Wilson (or Britton & Wilson).

46C.2.  After a name published jointly by more than two authors, the citation
should be restricted to the first author followed by “et al.” or “& al.”, except in
the original publication.

Ex. 2.  Lapeirousia erythrantha var. welwitschii (Baker) Geerinck, Lisowski, Malaisse
& Symoens (in Bull. Soc. Roy. Bot. Belgique 105: 336. 1972) should be cited as
L. erythrantha var. welwitschii (Baker) Geerinck & al.

Recommendation 46D

46D.1.  Authors should cite themselves by name after each new name they pub-
lish rather than refer to themselves by expressions such as “nobis” (nob.) or
“mihi” (m.).

Article 47

47.1.  An alteration of the diagnostic characters or of the circumscription
of a taxon without the exclusion of the type does not warrant a change of
the author citation of the name of the taxon.

Ex. 1.  When the original material of Arabis beckwithii S. Watson (1887) is attributed to
two different species, as by Munz (1932), that species not including the lectotype must
bear a different name (A. shockleyi Munz) but the other one is still named A. beckwithii
S. Watson.

Ex. 2.  Myosotis as revised by Brown differs from the genus as originally circumscribed by
Linnaeus, but the generic name remains Myosotis L. since the type of the name is still
included in the genus (it may be cited as Myosotis L. emend. R. Br.: see Rec. 47A).

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Author citations 47-48

Ex. 3.  The variously defined species that includes the types of Centaurea jacea L. (1753),
C. amara L. (1763) and a variable number of other species names is still called C. jacea L.
(or L. emend. Coss. & Germ., L. emend. Vis., or L. emend. Godr., as the case may be: see
Rec. 47A).

Recommendation 47A

47A.1.  When an alteration as mentioned in Art. 47 has been considerable, the
nature of the change may be indicated by adding such words, abbreviated where
suitable, as “emendavit” (emend.) followed by the name of the author responsible
for the change, “mutatis characteribus” (mut. char.), “pro parte” (p. p.), “excluso
genere” or “exclusis generibus” (excl. gen.), “exclusa specie” or “exclusis specie-
bus” (excl. sp.), “exclusa varietate” or “exclusis varietatibus” (excl. var.), “sensu
amplo” (s. ampl.), “sensu lato” (s. l.), “sensu stricto” (s. str.), etc.

Ex. 1.  Phyllanthus L. emend. Müll. Arg.; Globularia cordifolia L. excl. var. (emend.
Lam.).

Article 48

48.1.  When an author adopts an existing name but definitely excludes its
original type, a later homonym that must be attributed solely to that author
is considered to have been published. Similarly, when an author who
adopts a name refers to an apparent basionym but explicitly excludes its
type, a new name is considered to have been published that must be at-
tributed solely to that author. Exclusion can be effected by simultaneous
explicit inclusion of the type in a different taxon by the same author (see
also Art. 59.6).

Ex. 1.  Sirodot (1872) placed the type of Lemanea Bory (1808) in Sacheria Sirodot (1872);
hence Lemanea, as treated by Sirodot (1872), is to be cited as Lemanea Sirodot non Bory
and not as Lemanea Bory emend. Sirodot.

Ex. 2.  The name Amorphophallus campanulatus Decne. (1834) was apparently based on
the illegitimate Arum campanulatum Roxb. (1819). However, the type of the latter was
explicitly excluded by Decaisne, and his name is therefore a legitimate name of a new
species, to be attributed solely to him.

Ex. 3.  Cenomyce ecmocyna Ach. (1810) is a superfluous name for Lichen gracilis L.
(1753), and so is Scyphophora ecmocyna Gray (1821), the type of L. gracilis still being
included. However, when proposing the combination Cladonia ecmocyna, Leighton (1866)
explicitly excluded that type and thereby published a new, legitimate name, Cladonia
ecmocyna
Leight.

Note 1.  Misapplication of a new combination to a different taxon, but without
explicit exclusion of the type of the basionym, is dealt with under Art. 7.4.

Note 2.  Retention of a name in a sense that excludes its original type, or its type
designated under Art. 7-10, can be effected only by conservation (see Art. 14.9).

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49-50 Author citations

Article 49

49.1.  When a genus or a taxon of lower rank is altered in rank but retains
its name or the final epithet in its name, the author of the earlier, name- or
epithet-bringing legitimate name (the author of the basionym) must be
cited in parentheses, followed by the name of the author who effected the
alteration (the author of the new name). The same holds when a taxon of
lower rank than genus is transferred to another genus or species, with or
without alteration of rank.

Ex. 1.  Medicago polymorpha var. orbicularis L. (1753) when raised to the rank of species
becomes M. orbicularis (L.) Bartal. (1776).

Ex. 2.  Anthyllis sect. Aspalathoides DC. (1825) raised to generic rank, retaining the epithet
Aspalathoides as its name, is cited as Aspalathoides (DC.) K. Koch (1853).

Ex. 3.  Cineraria sect. Eriopappus Dumort. (Fl. Belg.: 65. 1827) when transferred to
Tephroseris (Rchb.) Rchb. is cited as T. sect. Eriopappus (Dumort.) Holub (in Folia Geo-
bot. Phytotax. 8: 173. 1973).

Ex. 4.  Cistus aegyptiacus L. (1753) when transferred to Helianthemum Mill. is cited as
H. aegyptiacum (L.) Mill. (1768).

Ex. 5.  Fumaria bulbosa var. solida L. (1753) was elevated to specific rank as F. solida
(L.) Mill. (1771). The name of this species when transferred to Corydalis DC. is to be cited
as C. solida (L.) Clairv. (1811), not C. solida (Mill.) Clairv.

Ex. 6.  However, Pulsatilla montana var. serbica W. Zimm. (in Feddes Repert. Spec. Nov.
Regni Veg. 61: 95. 1958), originally placed under P. montana subsp. australis (Heuff.)
Zämelis, retains the same author citation when placed under P. montana subsp. dacica
Rummelsp. (see Art. 24.1) and is not cited as var. serbica “(W. Zimm.) Rummelsp.” (in
Feddes Repert. 71: 29. 1965).

Ex. 7.  Salix subsect. Myrtilloides C. K. Schneid. (Ill. Handb. Laubholzk. 1: 63. 1904),
originally placed under S. sect. Argenteae W. D. J. Koch, retains the same author citation
when placed under S. sect. Glaucae Pax and is not cited as S. subsect. Myrtilloides “(C.
K. Schneid.) Dorn” (in Canad. J. Bot. 54: 2777. 1976).

Note 1.  Art. 46.5 provides for the use of parenthetical author citations preceding
the word “ex”, after some names in groups with a starting point later than 1753.

Article 50

50.1.  When a taxon at the rank of species or below is transferred from the
non-hybrid category to the hybrid category of the same rank (Art. H.10.2),
or vice versa, the author citation remains unchanged but may be followed
by an indication in parentheses of the original category.

Ex. 1.  Stachys ambigua Sm. (1809) was published as the name of a species. If regarded as
applying to a hybrid, it may be cited as Stachys ×ambigua Sm. (pro sp.).

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Author citations – Citation 50-50D

Ex. 2.  The binary name Salix ×glaucops Andersson (1868) was published as the name of a
hybrid. Later, Rydberg (in Bull. New York Bot. Gard. 1: 270. 1899) considered the taxon
to be a species. If this view is accepted, the name may be cited as Salix glaucops Anders-
son (pro hybr.).

SECTION 4. GENERAL RECOMMENDATIONS ON CITATION

Recommendation 50A

50A.1.  In the citation of a name invalidly published as a synonym, the words “as
synonym” or “pro syn.” should be added.

Recommendation 50B

50B.1.  In the citation of a nomen nudum, its status should be indicated by adding
the words “nomen nudum” or “nom. nud.”

Ex. 1.  “Carex bebbii” (Olney, Car. Bor.-Am. 2: 12. 1871), published without a descrip-
tion or diagnosis, should be cited as Carex bebbii Olney, nomen nudum (or nom. nud.).

Recommendation 50C

50C.1.  The citation of a later homonym should be followed by the name of the
author of the earlier homonym preceded by the word “non”, preferably with the
date of publication added. In some instances it will be advisable to cite also any
other homonyms, preceded by the word “nec”.

Ex. 1.  Ulmus racemosa Thomas in Amer. J. Sci. Arts 19: 170. 1831, non Borkh. 1800;
Lindera Thunb., Nov. Gen. Pl.: 64. 1783, non Adans. 1763; Bartlingia Brongn. in Ann.
Sci. Nat. (Paris) 10: 373. 1827, non Rchb. 1824 nec F. Muell. 1882.

Recommendation 50D

50D.1.  Misidentifications should not be included in synonymies but added after
them. A misapplied name should be indicated by the words “auct. non” followed
by the name of the original author and the bibliographic reference of the misiden-
tification.

Ex. 1.  Ficus stortophylla Warb. in Ann. Mus. Congo Belge, B, Bot., ser. 4, 1: 32. 1904. F.
irumuënsis
De Wild., Pl. Bequaert. 1: 341. 1922. F. exasperata auct. non Vahl: De
Wildeman & Durand in Ann. Mus. Congo Belge, B, Bot., ser. 2, 1: 54. 1899; De Wilde-
man, Miss. Em. Laurent: 26. 1905; Durand & Durand, Syll. Fl. Congol.: 505. 1909.

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50E-50F Citation

Recommendation 50E

50E.1.  If a name of a family, genus, or species is accepted as a nomen conser-
vandum
(see Art. 14 and App. II-III) the abbreviation “nom. cons.” should be
added in a full citation.

Ex. 1.  Protea L., Mant. Pl.: 187. 1771, nom. cons., non L. 1753; Combretum Loefl.
(1758), nom. cons. [= Grislea L. 1753].

50E.2.  If a name has been adopted by Fries or Persoon, and thereby sanctioned
(see Art. 13.1(d) and 7.8), “: Fr.” or “: Pers.” should be added in a full citation.
The same convention should be used for the basionym of the sanctioned name, if
it has one, and for all combinations based on either the sanctioned name or its
basionym.

Ex. 2.  Boletus piperatus Bull. (Herb. France: t. 451, f. 2. 1790) was accepted in Fries
(Syst. Mycol. 1: 388. 1821) and was thereby sanctioned. It should thus be cited as B. pipe-
ratus
Bull. : Fr., and a subsequent combination based on it, as Chalciporus piperatus
(Bull. : Fr.) Bataille.

Ex. 3.  Agaricus sarcocephalus Fr. 1815 : Fr. was sanctioned as Agaricus compactus [un-
ranked] sarcocephalus (Fr. : Fr.) Fr. 1821; Psathyrella sarcocephala (Fr. : Fr.) Singer is a
subsequent combination based on it.

Recommendation 50F

50F.1.  If a name is cited with alterations from the form as originally published, it
is desirable that in full citations the exact original form should be added, prefera-
bly between single or double quotation marks.

Ex. 1.  Pyrus calleryana Decne. (P. mairei H. Lév. in Repert. Spec. Nov. Regni Veg. 12:
189. 1913, “Pirus”).

Ex. 2.  Zanthoxylum cribrosum Spreng., Syst. Veg. 1: 946. 1825, “Xanthoxylon”. (Z. ca-
ribaeum
var. floridanum (Nutt.) A. Gray in Proc. Amer. Acad. Arts 23: 225. 1888, “Xan-
thoxylum”)
.

Ex. 3.  Spathiphyllum solomonense Nicolson in Amer. J. Bot. 54: 496. 1967, “solomonen-
sis”
.

 
 
 
 
 
 
 
 
 

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Maintenance – Illegitimacy 51-52

 
 
 
 
 

CHAPTER V. REJECTION OF NAMES

Article 51

51.1.  A legitimate name must not be rejected merely because it, or its
epithet, is inappropriate or disagreeable, or because another is preferable
or better known (but see Art. 56.1), or because it has lost its original
meaning, or (in pleomorphic fungi with names governed by Art. 59) be-
cause the generic name does not accord with the morph represented by its
type.

Ex. 1.  The following changes are contrary to the rule: Staphylea to Staphylis, Tamus to
Thamnos, Thamnus, or Tamnus, Mentha to Minthe, Tillaea to Tillia, Vincetoxicum to Ale-
xitoxicum;
and Orobanche rapum to O. sarothamnophyta, O. columbariae to O. colum-
barihaerens, O. artemisiae
to O. artemisiepiphyta.

Ex. 2.  Ardisia quinquegona Blume (1825) is not to be changed to A. pentagona A. DC.
(1834), although the specific epithet quinquegona is a hybrid word (Latin and Greek)
(contrary to Rec. 23A.3(c)).

Ex. 3.  The name Scilla peruviana L. (1753) is not to be rejected merely because the spec-
ies does not grow in Peru.

Ex. 4.  The name Petrosimonia oppositifolia (Pall.) Litv. (1911), based on Polycnemum
oppositifolium
Pall. (1771), is not to be rejected merely because the species has leaves only
partly opposite, and partly alternate, although there is another closely related species,
Petrosimonia brachiata (Pall.) Bunge, having all its leaves opposite.

Ex. 5.  Richardia L. (1753) is not to be changed to Richardsonia, as was done by Kunth
(1818), although the name was originally dedicated to the British botanist, Richardson.

Article 52

52.1.  A name, unless conserved (Art. 14) or sanctioned (Art. 15), is ille-
gitimate and is to be rejected if it was nomenclaturally superfluous when
published, i.e. if the taxon to which it was applied, as circumscribed by its
author, definitely included the type (as qualified in Art. 52.2) of a name
which ought to have been adopted, or of which the epithet ought to have
been adopted, under the rules (but see Art. 52.3).

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52 Illegitimacy

52.2.  For the purpose of Art. 52.1, definite inclusion of the type of a name
is effected by citation (a) of the holotype under Art 9.1 or the original
type under Art. 10 or all syntypes under Art. 9.4 or all elements eligible as
types under Art. 10.2; or (b) of the previously designated type under Art.
9.9-11 or 10.2; or (c) of the previously conserved type under Art 14.9; or
(d) of the illustrations of these. It is also effected (e) by citation of the
name itself, unless the type is at the same time excluded either explicitly
or by implication.

Ex. 1.  The generic name Cainito Adans. (1763) is illegitimate because it was a superflu-
ous name for Chrysophyllum L. (1753), which Adanson cited as a synonym.

Ex. 2.  Chrysophyllum sericeum Salisb. (1796) is illegitimate, being a superfluous name for
C. cainito L. (1753), which Salisbury cited as a synonym.

Ex. 3.  On the other hand, Salix myrsinifolia Salisb. (1796) is legitimate, being explicitly
based upon S. myrsinites of Hoffmann (Hist. Salic. Ill.: 71. 1787), a misapplication of the
name S. myrsinites L. (1753).

Ex. 4.  Picea excelsa Link (1841) is illegitimate because it is based on Pinus excelsa Lam.
(1778), a superfluous name for Pinus abies L. (1753). Under Picea the correct name is
Picea abies (L.) H. Karst. (1881).

Ex. 5.  On the other hand, Cucubalus latifolius Mill. and C. angustifolius Mill. are not
illegitimate names, although Miller’s species are now united with the species previously
named C. behen L. (1753): C. latifolius and C. angustifolius as circumscribed by Miller
(1768) did not include the type of C. behen L., which name he adopted for another species.

Ex. 6.  Explicit exclusion of type: When publishing the name Galium tricornutum, Dandy
(in Watsonia 4: 47. 1957) cited G. tricorne Stokes (1787) pro parte as a synonym, but ex-
plicitly excluded the type of the latter name.

Ex. 7.  Exclusion of type by implication: Tmesipteris elongata P. A. Dang. (in Botaniste 2:
213. 1891) was published as a new species but Psilotum truncatum R. Br. was cited as a
synonym. However, on the following page, T. truncata (R. Br.) Desv. is recognized as a
different species and two pages later both are distinguished in a key, thus showing that the
meaning of the cited synonym was either “P. truncatum R. Br. pro parte” or “P. truncatum
auct. non R. Br.”

Ex. 8.  Exclusion of type by implication: Solanum torvum Sw. (Prodr.: 47. 1788) was
published with a new diagnosis but S. indicum L. (1753) was cited as a synonym. In accord
with the practice in his Prodromus, Swartz indicated where the species was to be inserted
in the latest edition [ed. 14, by Murray] of Linnaeus’s Systema vegetabilium. S. torvum
was to be inserted between species 26 (S. insanum) and 27 (S. ferox), the number of S. in-
dicum
being 32. S. torvum is thus a legitimate name.

Note 1.  The inclusion, with an expression of doubt, of an element in a new taxon,
e.g. the citation of a name with a question mark, does not make the name of the
new taxon nomenclaturally superfluous.

Ex. 9.  The protologue of Blandfordia grandiflora R. Br. (1810) includes, in synonymy,
“Aletris punicea. Labill. nov. holl. 1. p. 85. t. 111 ?”, indicating that the new species might be
the same as Aletris punicea Labill. (1805). B. grandiflora is nevertheless a legitimate name.

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Illegitimacy – Homonymy 52-53

Note 2.  The inclusion, in a new taxon, of an element that was subsequently des-
ignated as the type of a name which, so typified, ought to have been adopted, or
of which the epithet ought to have been adopted, does not in itself make the name
of the new taxon illegitimate.

Ex. 10.  Leccinum Gray (1821) does not include all potential types (in fact, none) of
Boletus L. (1753) and thus is not illegitimate, even though it included, as L. edule (Bull. :
Fr.) Gray, the subsequently conserved type of Boletus, B. edulis Bull. : Fr.

52.3.  A name that was nomenclaturally superfluous when published is not
illegitimate if its basionym is legitimate, or if it is based on the stem of a
legitimate generic name. When published it is incorrect, but it may be-
come correct later.

Ex. 11.  Chloris radiata (L.) Sw. (1788), based on Agrostis radiata L. (1759), was nomen-
claturally superfluous when published, since Swartz also cited Andropogon fasciculatus L.
(1753) as a synonym. It is, however, the correct name in the genus Chloris for Agrostis
radiata
when Andropogon fasciculatus is treated as a different species, as was done by
Hackel (in Candolle & Candolle, Monogr. Phan. 6: 177. 1889).

Ex. 12.  The generic name Hordelymus (K. Jess.) K. Jess. (1885), based on the legitimate
Hordeum subg. Hordelymus K. Jess. (Deutschl. Gräser: 202. 1863), was superfluous when
published because its type, Elymus europaeus L., is also the type of Cuviera Koeler (1802).
Cuviera Koeler has since been rejected in favour of its later homonym Cuviera DC.,
and Hordelymus can now be used as a correct name for the segregate genus contain-
ing Elymus europaeus L.

Note 3.  In no case does a statement of parentage accompanying the publication
of a name for a hybrid make the name illegitimate (see Art. H.5).

Ex. 13.  The name Polypodium ×shivasiae Rothm. (1962) was proposed for hybrids be-
tween P. australe Fée and P. vulgare subsp. prionodes (Asch.) Rothm., while at the same
time the author accepted P. ×font-queri Rothm. (1936) for hybrids between P. australe and
P. vulgare L. subsp. vulgare. Under Art. H.4.1, P. ×shivasiae is a synonym of P. ×font-
queri;
nevertheless, it is not an illegitimate name.

Article 53

53.1.  A name of a family, genus or species, unless conserved (Art. 14) or
sanctioned (Art. 15), is illegitimate if it is a later homonym, that is, if it is
spelled exactly like a name based on a different type that was previously
and validly published for a taxon of the same rank (see also Art. 6 Note 1).

Ex. 1.  The name Tapeinanthus Boiss. ex Benth. (1848), given to a genus of Labiatae, is a
later homonym of Tapeinanthus Herb. (1837), a name previously and validly published for
a genus of Amaryllidaceae. Tapeinanthus Boiss. ex Benth. is therefore unavailable for use.
It was renamed Thuspeinanta T. Durand (1888).

Ex. 2.  The name Torreya Arn. (1838) is a nomen conservandum and is therefore available
for use in spite
of the existence of the earlier homonym Torreya Raf. (1818).

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53 Homonymy

Ex. 3.  Astragalus rhizanthus Boiss. (1843) is a later homonym of the validly published
name Astragalus rhizanthus Royle (1835) and is therefore unavailable for use. Boissier re-
named it A. cariensis Boiss. (1849).

Note 1.  A later homonym is unavailable for use even if the earlier homonym is
illegitimate or is otherwise generally treated as a synonym.

Ex. 4.  Zingiber truncatum S. Q. Tong (1987) is illegitimate, being a later homonym of Z. trun-
catum
Stokes (1812), even though the latter name is itself illegitimate under Art 52.1 because
in its protologue the name Amomum zedoaria Christm. (1779) was cited in synonymy.

Ex. 5.  The name Amblyanthera Müll. Arg. (1860) is a later homonym of the validly pub-
lished Amblyanthera Blume (1849) and is therefore unavailable for use, although Ambly-
anthera
Blume is now considered to be a synonym of Osbeckia L. (1753).

53.2.  A sanctioned name is illegitimate if it is a later homonym of another
sanctioned name (see also Art. 15 Note 1).

53.3.  When two or more generic or specific names based on different
types are so similar that they are likely to be confused (because they are
applied to related taxa or for any other reason) they are to be treated as
homonyms (see also Art. 61.5).

*Ex. 6.  Names treated as homonyms: Asterostemma Decne. (1838) and Astrostemma
Benth. (1880); Pleuropetalum Hook. f. (1846) and Pleuripetalum T. Durand (1888);
Eschweilera DC. (1828) and Eschweileria Boerl. (1887); Skytanthus Meyen (1834) and
Scytanthus Hook. (1844).

*Ex. 7.  The three generic names Bradlea Adans. (1763), Bradleja Banks ex Gaertn.
(1790), and Braddleya Vell. (1827), all commemorating Richard Bradley, are treated as
homonyms because only one can be used without serious risk of confusion.

*Ex. 8.  The names Acanthoica Lohmann (1902) and Acanthoeca W. N. Ellis (1930), both des-
ignating flagellates, are sufficiently alike to be considered homonyms (Taxon 22: 313. 1973).

*Ex. 9.  Epithets so similar that they are likely to be confused if combined under the same
generic or specific name: chinensis and sinensis; ceylanica and zeylanica; napaulensis, ne-
palensis,
and nipalensis; polyanthemos and polyanthemus; macrostachys and macrosta-
chyus;
heteropus and heteropodus; poikilantha and poikilanthes; pteroides and pteroideus;
trinervis and trinervius; macrocarpon and macrocarpum; trachycaulum and trachycaulon.

*Ex. 10.  Names not likely to be confused: Rubia L. (1753) and Rubus L. (1753); Mono-
chaetum
(DC.) Naudin (1845) and Monochaete Döll (1875); Peponia Grev. (1863) and
Peponium Engl. (1897); Iris L. (1753) and Iria (Pers.) Hedw. (1806); Desmostachys Miers
(1852) and Desmostachya (Stapf) Stapf (1898); Symphyostemon Miers (1841) and Sym-
phostemon
Hiern (1900); Gerrardina Oliv. (1870) and Gerardiina Engl. (1897); Urvillea
Kunth (1821) and Durvillaea Bory (1826); Peltophorus Desv. (1810; Gramineae) and
Peltophorum (Vogel) Benth. (1840; Leguminosae); Senecio napaeifolius (DC.) Sch. Bip.
(1845, “napeaefolius”; see Art 60. Ex. 14) and S. napifolius MacOwan (1890; the epithets
being derived, respectively, from Napaea and Brassica napus); Lysimachia hemsleyana
Oliv. (1891) and L. hemsleyi Franch. (1895) (see, however, Rec. 23A.2); Euphorbia peplis
L. (1753) and E. peplus L. (1753).

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Homonymy 53

Ex. 11.  Names conserved against earlier names treated as homonyms (see App. IIIA):
Lyngbya Gomont (vs. Lyngbyea Sommerf.); Columellia Ruiz & Pav. (vs. Columella
Lour.), both commemorating Columella, the Roman writer on agriculture; Cephalotus
Labill. (vs. Cephalotos Adans.); Simarouba Aubl. (vs. Simaruba Boehm.).

53.4.  The names of two subdivisions of the same genus, or of two in-
fraspecific taxa within the same species, even if they are of different rank,
are treated as homonyms if they have the same or a confusingly similar
epithet and are not based on the same type.

Ex. 12.  The names Andropogon sorghum subsp. halepensis (L.) Hack. and A. sorghum
var. halepensis (L.) Hack. (in Candolle & Candolle, Monogr. Phan. 6: 502. 1889) are
legitimate, since both have the same type and the epithet may be repeated under Rec.
26A.1.

Ex. 13.  Anagallis arvensis var. caerulea (L.) Gouan (Fl. Monsp.: 30. 1765), based on
A. caerulea L. (1759), makes illegitimate the name A. arvensis subsp. caerulea Hartm.
(Sv. Norsk Exc.-Fl.: 32. 1846), based on the later homonym A. caerulea Schreber (1771).

Ex. 14.  Scenedesmus armatus var. brevicaudatus (Hortob.) Pankow (in Arch. Protistenk.
132: 153. 1986), based on S. carinatus var. brevicaudatus Hortob. (in Acta Bot. Acad. Sci.
Hung. 26: 318. 1981), is a later homonym of S. armatus f. brevicaudatus L. S. Péterfi (in
Stud. Cercet. Biol. (Bucharest), Ser. Biol. Veg. 15: 25. 1963) even though the two names
apply to taxa of different infraspecific rank. Scenedesmus armatus var. brevicaudatus (L.
S. Péterfi) E. H. Hegew. (in Arch. Hydrobiol. Suppl. 60: 393. 1982), however, is not a later
homonym since it is based on the same type as S. armatus f. brevicaudatus L. S. Péterfi.

Note 2.  The same final epithet may be used in the names of subdivisions of dif-
ferent genera, and of infraspecific taxa within different species.

Ex. 15.  Verbascum sect. Aulacosperma Murb. (Monogr. Verbascum: 34, 593. 1933) is
permissible, although there is an earlier Celsia sect. Aulacospermae Murb. (Monogr. Cel-
sia: 34, 56. 1926). This, however, is not an example to be followed, since it is contrary to
Rec 21B.2.

53.5.  When it is doubtful whether names or their epithets are sufficiently
alike to be confused, a request for a decision may be submitted to the
General Committee (see Div. III), which will refer it for examination
to the committee or committees for the appropriate taxonomic group or
groups. A recommendation may then be put forward to an International
Botanical Congress, and, if ratified, will become a binding decision.

Ex. 16.  Names ruled as likely to be confused, and therefore to be treated as homonyms:
Ficus gomelleira Kunth (1847) and F. gameleira Standl. (1937) (Taxon 42: 111. 1993);
Solanum saltiense S. Moore (1895) and S. saltense (Bitter) C. V. Morton (1944) (Taxon
42: 434. 1993); Balardia Cambess. (1829; Caryophyllaceae) and Ballardia Montrouz.
(1860; Myrtaceae) (Taxon 42: 434. 1993).

Ex. 17.  Names ruled as not likely to be confused: Cathayeia Ohwi (1931; Flacourtiaceae
and Cathaya Chun & Kuang (1962; fossil Pinaceae) (Taxon 36: 429. 1987); Cristella Pat.
(1887; Fungi) and Christella H. Lév. (1915; Pteridophyta) (Taxon 35: 551. 1986); Coluria

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53-54 Homonymy

R. Br. (1823; Rosaceae) and Colura (Dumort.) Dumort. (1835; Hepaticae) (Taxon 42:
433. 1993); Acanthococcus Hook. f. & Harv. (1845; Rhodophyta) and Acanthococos Barb.
Rodr. (1900; Palmae) (Taxon 42: 433. 1993); Rauia Nees & Mart. (1823; Rutaceae) and
Rauhia Traub (1957; Amaryllidaceae) (Taxon 42: 433. 1993).

53.6.  When two or more homonyms have equal priority, the first of them
that is adopted in an effectively published text (Art. 29-31) by an author
who simultaneously rejects the other(s) is treated as having priority. Like-
wise, if an author in an effectively published text substitutes other names
for all but one of these homonyms, the homonym for the taxon that is not
renamed is treated as having priority.

Ex. 18.  Linnaeus simultaneously published “10.” Mimosa cinerea (Sp. Pl.: 517. 1753) and
“25.” M. cinerea (Sp. Pl.: 520. 1753). In 1759, he renamed species 10 M. cineraria L. and
retained the name M. cinerea for species 25, so that the latter is treated as having priority
over its homonym.

Ex. 19.  Rouy & Foucaud (Fl. France 2: 30. 1895) published the name Erysimum hieracii-
folium
var. longisiliquum, with two different types, for two different taxa under different
subspecies. Only one of these names can be maintained.

Note 3.  A homonym renamed or rejected under Art. 53.6 remains legitimate and
takes precedence over a later synonym of the same rank, should a transfer to an-
other genus or species be effected.

Ex. 20.  Mimosa cineraria L. (1759), based on M. cinerea L. (Sp. Pl.: 517 [non 520]. 1753;
see Art. 53 Ex. 18), was transferred to Prosopis by Druce (1914) as P. cineraria (L.)
Druce. However, the correct name in Prosopis is a combination based on M. cinerea.

Article 54

54.1.  Consideration of homonymy does not extend to the names of taxa
not treated as plants, except as stated below:

(a)  Later homonyms of the names of taxa once treated as plants are ille-
      gitimate, even though the taxa have been reassigned to a different
      group of organisms to which this Code does not apply.

(b)  A name originally published for a taxon other than a plant, even if
      validly published under Art. 32-45 of this Code, is illegitimate if it be-
      comes a homonym of a plant name when the taxon to which it applies
      is first treated as a plant (see also Art. 45.4).

Note 1.  The International code of nomenclature of bacteria provides that a bacte-
rial name is illegitimate if it is a later homonym of a name of a taxon of bacteria,
fungi, algae, protozoa, or viruses.

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Homonymy – Rejection 54A-56

Recommendation 54A

54A.1.  Authors naming new botanical taxa should, as far as is practicable, avoid
using such names as already exist for zoological and bacteriological taxa.

Article 55

55.1.  A name of a species or subdivision of a genus may be legitimate
even if its epithet was originally placed under an illegitimate generic name
(see also Art. 22.5).

Ex. 1.  Agathophyllum Juss. (1789) is an illegitimate name, being a superfluous substitute
for Ravensara Sonn. (1782). Nevertheless the name A. neesianum Blume (1851) is legiti-
mate. Because Meisner (1864) cited A. neesianum as a synonym of his new Mespilodaphne
mauritiana
but did not adopt the epithet neesiana, M. mauritiana Meisn. is a superfluous
name and hence illegitimate.

55.2.  An infraspecific name may be legitimate even if its final epithet was
originally placed under an illegitimate specific name (see also Art. 27.2).

55.3.  The names of species and of subdivisions of genera assigned to gen-
era the names of which are conserved or sanctioned later homonyms, and
which had earlier been assigned to the genera under the rejected homo-
nyms, are legitimate under the conserved or sanctioned names without
change of authorship or date if there is no other obstacle under the rules.

Ex. 2.  Alpinia languas J. F. Gmel. (1791) and Alpinia galanga (L.) Willd. (1797) are to be
accepted although Alpinia L. (1753), to which they were assigned by their authors, is rejected
and the genus in which they are now placed is named Alpinia Roxb. (1810), nom. cons.

Article 56

56.1.  Any name that would cause a disadvantageous nomenclatural change
(Art. 14.1) may be proposed for rejection. A name thus rejected, or its
basionym if it has one, is placed on a list of nomina utique rejicienda
(App. IV). Along with the listed names, all combinations based on them
are similarly rejected, and none is to be used.

56.2.  The list of rejected names will remain permanently open for additions
and changes. Any proposal for rejection of a name must be accompanied
by a detailed statement of the cases both for and against its rejection, in-
cluding considerations of typification. Such proposals must be submitted
to the General Committee (see Div. III), which will refer them for exami-
nation to the committees for the various taxonomic groups (see also Art.
14.14 and Rec. 14A).

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57-58 Rejection – Re-use

Article 57

57.1.  A name that has been widely and persistently used for a taxon or
taxa not including its type is not to be used in a sense that conflicts with
current usage unless and until a proposal to deal with it under Art. 14.1 or
56.1 has been submitted and rejected.

Article 58

58.1.  The epithet in an illegitimate name if available may be used in a
different combination, at the same or a different rank, if no other epithet is
available from a name that has priority at that rank. The resulting name is
then treated as new, either as a nomen novum with the same type as the
illegitimate name (see also Art. 7.5 and Art. 33 Note 2), or as the name of
a new taxon with a different type. Its priority does not date back to the
publication of the illegitimate name.

Ex. 1.  The name Talinum polyandrum Hook. (1855) is illegitimate, being a later homo-
nym of T. polyandrum Ruiz & Pav. (1798). When Bentham, in 1863, transferred T. poly-
andrum
Hook. to Calandrinia, he called it C. polyandra. This name has priority from
1863, and is cited as C. polyandra Benth., not C. polyandra (Hook.) Benth.

Ex. 2.  While describing Collema tremelloides var. cyanescens, Acharius (Syn. Meth.
Lich.: 326. 1814) cited C. tremelloides var. caesium Ach. (Lichenogr. Universalis: 656.
1810) in synonymy, thus rendering his new name illegitimate. The epithet cyanescens was
taken up in the combination Parmelia cyanescens Schaer. (1842), but this is a later homo-
nym of P. cyanescens (Pers.) Ach. (1803). In Collema, however, the specific epithet cya-
nescens
was available for use, and the name C. cyanescens Rabenh. (1845), based on the
same type, is legitimate. The correct author citation for Leptogium cyanescens, validated
by Körber (1855) by reference to C. cyanescens “Schaer.”, is therefore (Rabenh.) Körb.,
not (Ach.) Körb. nor (Schaer.) Körb.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Pleomorphic fungi 59

 
 
 
 

CHAPTER VI. NAMES OF FUNGI WITH A PLEOMORPHIC LIFE

CYCLE

Article 59

59.1.  In non lichen-forming ascomycetous and basidiomycetous fungi
(including Ustilaginales) with mitotic asexual morphs (anamorphs) as
well as a meiotic sexual morph (teleomorph), the correct name covering
the holomorph (i.e., the species in all its morphs) is the earliest legitimate
name typified by an element representing the teleomorph, i.e. the morph
characterized by the production of asci/ascospores, basidia/basidiospores,
teliospores, or other basidium-bearing organs.

Ex. 1.  The name Crocicreomyces guttiferae Bat. & Peres (1964) was published for a
lichen-forming fungus producing only a mitosporic asexual morph. When it was recog-
nized that C. guttiferae is conspecific with Byssoloma aeruginescens Vězda (1974), based
on an ascospore-producing type, and that Crocicreomyces Bat. & Peres (1964) is synony-
mous with Byssoloma Trevis. (1853), Batista & Peres’s epithet was correctly recombined
as B. guttiferae (Bat. & Peres) Lücking & Sérus. (1998). As Art. 59 does not apply to
lichen-forming fungi, no separate generic or specific names are available for use for the
mitosporic state.

59.2.  For a binary name to qualify as a name of a holomorph, not only must
its type specimen be teleomorphic, but also the protologue must include a
description or diagnosis of this morph (or be so phrased that the possibil-
ity of reference to the teleomorph cannot be excluded).

59.3.  If these requirements are not fulfilled, the name is that of a form-
taxon and is applicable only to the anamorph represented by its type, as
described or referred to in the protologue. The accepted taxonomic dispo-
sition of the type of the name determines the application of the name, no
matter whether the genus to which a subordinate taxon is assigned by the
author(s) is holomorphic or anamorphic.

59.4.  Irrespective of priority, names with a teleomorphic type take prece-
dence over names with an anamorphic type when both types are judged to
belong to the same holomorphic taxon.

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59 Pleomorphic fungi

59.5.  The provisions of this article shall not be construed as preventing
the publication and use of binary names for form-taxa when it is thought
necessary or desirable to refer to anamorphs alone.

Ex. 2.  Because the teleomorph of Gibberella stilboides W. L. Gordon & C. Booth (1971)
is only known from strains of the anamorph Fusarium stilboides Wollenw. (1924) mating
in culture, and has not been found in nature, it may be thought desirable to use the name of
the anamorph for the pathogen of Coffea.

Ex. 3.  Cummins (1971), in The rust fungi of cereals, grasses and bamboos, found it to be
neither necessary nor desirable to introduce new names of anamorphs under Aecidium
Pers. : Pers. and Uredo Pers. : Pers., for the aecial and uredinial stages of species of Puc-
cinia
Pers. : Pers. of which the telial stage (teleomorph) was known.

Note 1.  When not already available, specific or infraspecific names for ana-
morphs may be proposed at the time of publication of the name for the holomor-
phic fungus or later. The epithets may, if desired, be identical, as long as they are
not in homonymous combinations.

59.6.  As long as there is direct and unambiguous evidence for the delib-
erate introduction of a new morph judged by the author(s) to be correlated
with the morph typifying a purported basionym, and this evidence is
strengthened by fulfilment of all requirements in Art. 32-45 for valid pub-
lication of a name of a new taxon, any indication such as “comb. nov.” or
“nom. nov.” is regarded as a formal error, and the name introduced is
treated as that of a new taxon, and attributed solely to the author(s) there-
of. When only the requirements for valid publication of a new combina-
tion (Art. 33 and 34) have been fulfilled, the name is accepted as such and
based, in accordance with Art. 7.4, on the type of the declared or implicit
basionym.

Ex. 4.  The name Penicillium brefeldianum B. O. Dodge (1933), based on teleomorphic
and anamorphic material, is a valid and legitimate name of a holomorph, in spite of the
attribution of the species to a form-genus. It is legitimately combined in a holomorphic
genus as Eupenicillium brefeldianum (B. O. Dodge) Stolk & D. B. Scott (1967). P. bre-
feldianum
is not available for use in a restricted sense for the anamorph alone.

Ex. 5.  The name Ravenelia cubensis Arthur & J. R. Johnst. (1918), based on a specimen
bearing only uredinia (an anamorph), is a valid and legitimate name of an anamorph, in
spite of the attribution of the species to a holomorphic genus. It is legitimately combined in
a form-genus as Uredo cubensis (Arthur & J. R. Johnst.) Cummins (1956). R. cubensis is
not available for use inclusive of the teleomorph.

Ex. 6.  Mycosphaerella aleuritidis was published as “(Miyake) Ou comb. nov., syn. Cerco-
spora aleuritidis
Miyake” but with a Latin diagnosis of the teleomorph. The indication
“comb. nov.” is taken as a formal error, and M. aleuritidis S. H. Ou (1940) is accepted as a
validly published new specific name for the holomorph, typified by the teleomorphic
material described by Ou.

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Pleomorphic fungi 59-59A

Ex. 7.  Corticium microsclerotium was originally published as “(Matz) Weber, comb. nov.,
syn. Rhizoctonia microsclerotia Matz” with a description, only in English, of the teleo-
morph. Because of Art. 36, this may not be considered as the valid publication of the name
of a new species, and so C. microsclerotium (Matz) G. F. Weber (1939) must be consid-
ered a validly published and legitimate new combination based on the specimen of the
anamorph that typifies its basionym. C. microsclerotium G. F. Weber (1951), published
with a Latin description and a teleomorphic type, is an illegitimate later homonym.

Ex. 8.  Hypomyces chrysospermus Tul. (1860), presented as the name of a holomorph
without the indication “comb. nov.” but with explicit reference to Mucor chrysospermus
(Bull.) Bull. and Sepedonium chrysospermum (Bull.) Fr., which are names of its ana-
morph, is not to be considered as a new combination but as the name of a newly described
species, with a teleomorphic type.

Recommendation 59A

59A.1.  When a new morph of a fungus is described, it should be published either
as a new taxon (e.g., gen. nov., sp. nov., var. nov.) the name of which has a
teleomorphic type, or as a new anamorph (anam. nov.) the name of which has an
anamorphic type.

59A.2.  When in naming a new morph of a fungus the epithet of the name of a
different, earlier described morph of the same fungus is used, the new name
should be designated as the name of a new taxon or anamorph, as the case may
be, but not as a new combination based on the earlier name.

59A.3.  Authors should avoid the publication and use of binary names for ana-
morphs when the teleomorphic connection is firmly established and there is no
practical need for separate names (as e.g. in rust fungi and members of the Tri-
chocomaceae
).

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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60 Orthography

 
 
 
 

CHAPTER VII. ORTHOGRAPHY AND GENDER OF NAMES

SECTION 1. ORTHOGRAPHY

Article 60

60.1.  The original spelling of a name or epithet is to be retained, except
for the correction of typographical or orthographical errors and the stan-
dardizations imposed by Art. 60.5 (u/v or i/j used interchangeably), 60.6
(diacritical signs and ligatures), 60.8 (compounding forms), 60.9 (hy-
phens), 60.10 (apostrophes), 60.11 (terminations; see also Art. 32.5), and
60.12 (fungal epithets)
.

Ex. 1.  Retention of original spelling: The generic names Mesembryanthemum L. (1753)
and Amaranthus L. (1753) were deliberately so spelled by Linnaeus and the spelling is not
to be altered to “Mesembrianthemum” and “Amarantus”, respectively, although these
latter forms are philologically preferable (see Bull. Misc. Inform. Kew 1928: 113, 287.
1928). – Phoradendron Nutt. (1848) is not to be altered to “Phoradendrum”. – Triaspis
mozambica
A. Juss. (1843) is not to be altered to “T. mossambica”, as in Engler (Pflan-
zenw. Ost-Afrikas C: 232. 1895). – Alyxia ceylanica Wight (1848) is not to be altered to
“A. zeylanica”, as in Trimen (Handb. Fl. Ceylon 3: 127. 1895). – Fagus sylvatica L.
(1753) is not to be altered to “F. silvatica”. The classical spelling silvatica is recom-
mended for adoption in the case of a new name (Rec. 60E), but the mediaeval spelling
sylvatica is not an orthographical error. – Scirpus cespitosus L. (1753) is not to be altered
to “S. caespitosus”.

*Ex. 2.  Typographical errors: Globba “brachycarpa” Baker (1890) and Hetaeria “alba”
Ridl. (1896) are typographical errors for Globba trachycarpa Baker and Hetaeria alta
Ridl., respectively (see J. Bot. 59: 349. 1921).

Ex. 3.  The misspelled Indigofera “longipednnculata” Y. Y. Fang & C. Z. Zheng (1983) is
presumably a typographical error and is to be corrected to I. longipedunculata.

*Ex. 4.  Orthographical error: Gluta “benghas” L. (1771), being an orthographical error
for G. renghas, is cited as G. renghas L. (see Engler in Candolle & Candolle, Monogr.
Phan. 4: 225. 1883); the vernacular name used as a specific epithet by Linnaeus is
“renghas”, not “benghas”.

Note 1.  Art. 14.11 provides for the conservation of an altered spelling of a name
of a family, genus, or species.

Ex. 5.  Bougainvillea (see App. IIIA, Spermatophyta, Dicotyledones).

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Orthography 60

60.2.  The words “original spelling” in this Article mean the spelling em-
ployed when the name was validly published. They do not refer to the use
of an initial capital or lower-case letter, this being a matter of typography
(see Art. 20.1 and 21.2, Rec. 60F).

60.3.  The liberty of correcting a name is to be used with reserve, espe-
cially if the change affects the first syllable and, above all, the first letter
of the name.

*Ex. 6.  The spelling of the generic name Lespedeza Michx. (1803) is not to be altered,
although it commemorates Vicente Manuel de Céspedes (see Rhodora 36: 130-132, 390-
392. 1934). – Cereus jamacaru DC. (1828) may not be altered to C. “mandacaru”, even if
jamacaru is believed to be a corruption of the vernacular name “mandacaru”.

60.4.  The letters w and y, foreign to classical Latin, and k, rare in that
language, are permissible in Latin plant names. Other letters and ligatures
foreign to classical Latin that may appear in Latin plant names, such as the
German ß (double s), are to be transcribed.

60.5.  When a name has been published in a work where the letters u, v or
i, j are used interchangeably or in any other way incompatible with mod-
ern practices (e.g., one letter of a pair not being used in capitals, or not at
all
), those letters are to be transcribed in conformity with modern botani-
cal usage.

Ex. 7.  Uffenbachia Fabr. (1763), not “Vffenbachia”; Taraxacum Zinn (1757), not “Tarax-
acvm”;
Curculigo Gaertn. (1788), not “Cvrcvligo”.

Ex. 8.  “Geastrvm hygrometricvm” and “Vredo pvstvlata” of Persoon (1801) are written,
respectively, Geastrum hygrometricum Pers. and Uredo pustulata Pers.

60.6.  Diacritical signs are not used in Latin plant names. In names (either
new or old) drawn from words in which such signs appear, the signs are to
be suppressed with the necessary transcription of the letters so modified;
for example ä, ö, ü become, respectively, ae, oe, ue; é, è, ê become e, or
sometimes ae; ñ becomes n; ø becomes oe; å becomes ao. The diaeresis,
indicating that a vowel is to be pronounced separately from the preceding
vowel (as in Cephaëlis, Isoëtes), is permissible; the ligatures -æ- and -œ-,
indicating that the letters are pronounced together, are to be replaced by
the separate letters -ae- and -oe-.

60.7.  When changes in spelling by authors who adopt personal, geo-
raphic, or vernacular names in nomenclature are intentional latinizations,
they are to be preserved, except when they concern only the termination
of epithets to which Art. 60.11 applies.

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60 Orthography

Ex. 9.  Clutia L. (1753), Gleditsia L. (1753), and Valantia L. (1753), commemorating
Cluyt, Gleditsch, and Vaillant, respectively, are not to be altered to “Cluytia”,
“Gleditschia”, and “Vaillantia”; Linnaeus latinized the names of these botanists deliber-
ately as Clutius, Gleditsius, and Valantius.

Ex. 10.  Abutilon glaziovii K. Schum. (1891), Desmodium bigelovii A. Gray (1843), and
Rhododendron bureavii Franch. (1887), commemorating A. F. M. Glaziou, J. Bigelow,
and L. E. Bureau, respectively, are not to be changed to A. “glazioui”, D. “bigelowii”, or
R. “bureaui”. In these three cases, the implicit latinizations Glaziovius, Bigelovius, and
Bureavius do not affect merely the termination of the names.

Ex. 11.  Blandfordia “backhousii”, Cephalotaxus “fortuni”, Chenopodium “loureirei”,
Convolvulus “loureiri”,
Glochidion “melvilliorum”,
and Zygophyllum “billardierii” were
published to commemorate J. Backhouse, R. Fortune, J. de Loureiro,
R. Melville and E.
F. Melville, and J. J. H. de Labillardière (de la Billardière). The implicit latinizations are
Backhousius, Fortunus, Loureirus or Loureireus, Melvillius, and Billardierius, but they
affect only the
termination and are not acceptable under Art. 60.11. The names are cor-
rectly cited as B. backhousei Gunn & Lindl. (1845), Cephalotaxus fortunei Hook. (1850),
Chenopodium loureiroi Steud. (1840), Convolvulus loureiroi G. Don (1836),
G. melvil-
leorum Airy Shaw (1971), and Z. billardierei DC. (1824).

Ex. 12.  Abies alcoquiana Veitch ex Lindl. (1861), commemorating “Rutherford Alcock
Esq.”, implies an intentional latinization of that name to Alcoquius. In transferring the
epithet to Picea, Carrière (1867) deliberately changed the spelling to “alcockiana”. The
resulting combination is nevertheless correctly cited as P. alcoquiana (Veitch ex Lindl.)
Carrière (see Art. 61.4).

60.8.  The use of a compounding form contrary to Rec. 60G in an adjecti-
val epithet is treated as an error to be corrected.

Ex. 13.  Candolle’s Pereskia “opuntiaeflora” is to be cited as P. opuntiiflora DC. (1828),
and Myrosma “cannaefolia” of the younger Linnaeus, as M. cannifolia L. f. (1782)
.

Ex. 14.  Cacalia “napeaefolia” and Senecio “napeaefolius” are to be cited as Cacalia
napaeifolia
DC. (1838) and Senecio napaeifolius (DC.) Sch. Bip. (1845), respectively; the
specific epithet refers to the resemblance of the leaves to those of the genus Napaea L. (not
“Napea”), and the substitute (connecting) vowel -i should have been used instead of the
genitive singular inflection -ae.

Ex. 15.  However, in Andromeda polifolia L. (1753), the epithet is a pre-Linnean plant
name (“Polifolia” of Buxbaum) used in apposition and not an adjective; it is not to be
altered to “poliifolia” (Polium-leaved).

60.9.  The use of a hyphen in a compound epithet is treated as an error to
be corrected by deletion of the hyphen, unless the epithet is formed of
words that usually stand independently or the letters before and after the
hyphen are the same, when a hyphen is permitted (see Art. 23.1 and 23.3).

Ex. 16.  Hyphen to be omitted:  Acer pseudoplatanus L. (1753), not A. “pseudo-platanus”;
Eugenia costaricensis O. Berg, not E. “costa-ricensis”; Ficus neoëbudarum Summerh.
(1932), not F. “neo-ebudarum”; Lycoperdon atropurpureum Vittad. (1842), not L. “atro-pur-
pureum”; Croton ciliatoglandulifer
Ortega (1797), not C. “ciliato-glandulifer”; Scirpus

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Orthography 60

sect. Pseudoëriophorum Jurtzev (in Bjull. Moskovsk. Obšč. Isp. Prir., Otd. Biol. 70(1):
132. 1965), not S. sect. “Pseudo-eriophorum”.

Ex. 17.  Hyphen to be maintained: Aster novae-angliae L. (1753), Coix lacryma-jobi L.
(1753), Arctostaphylos uva-ursi (L.) Spreng. (1825), Veronica anagallis-aquatica L.
(1753; Art. 23.3), Athyrium austro-occidentale Ching (1986).

Note 2.  Art. 60.9 refers only to epithets (in combinations), not to names of genera
or taxa in higher ranks; a generic name published with a hyphen can be changed
only by conservation (Art. 14.11).

Ex. 18.  Pseudo-salvinia Piton (1940) may not be changed to “Pseudosalvinia”;
“Pseudo-elephantopus” was changed by conservation to Pseudelephantopus Rohr (1792).

60.10.  The use of an apostrophe in an epithet is treated as an error to be
corrected by deletion of the apostrophe.

Ex. 19.  Lycium “o’donellii”, Cymbidium “i’ansoni” and Solanum tuberosum var. “mu-
ru’kewillu”
are to be corrected to L. odonellii F. A. Barkley (1953), C. iansonii Rolfe
(1900) and S. tuberosum var. murukewillu Ochoa (in Phytologia 65: 112. 1988), respec-
tively.

60.11.  The use of a termination (for example -i, -ii, -ae, -iae, -anus, or
-ianus) contrary to Rec. 60C.1 (but not 60C.2) is treated as an error to be
corrected (see also Art. 32.5).

Ex. 20.  Rosa “pissarti” (Carrière in Rev. Hort. 1880: 314. 1880) is a typographical error
for R. “pissardi” (see Rev. Hort. 1881: 190. 1881), which in its turn is treated as an error
for R. pissardii Carrière (see Rec. 60C.1(b)).

Ex. 21.  However, Uladendron codesuri Marc.-Berti (1971) is not to be changed to U. “co-
desurii”
(as by Brenan in Index Kew., Suppl. 16. 1981), since the epithet does not com-
memorate a person but derives from an acronym (CODESUR, Comisión para el Desarrollo
del Sur de Venezuela).

Ex. 22.  Asparagus tamaboki Yatabe (1893) bears the Japanese vernacular name “tama-
boki” as its epithet and is therefore not correctable to A. “tamabokii”.

Note 3.  If the gender and/or number of a substantival epithet derived from a
personal name is inappropriate for the sex and/or number of the person(s) whom
the name commemorates, the termination is to be corrected in conformity with
Rec. 60C.1.

Ex. 23.  Rosa דtoddii” was named by Wolley-Dod (in J. Bot. 69, Suppl.: 106. 1931) for
“Miss E. S. Todd”; the name is to be corrected to R. ×toddiae Wolley-Dod.

Ex. 24.  Astragalus “matthewsii”, published by Podlech and Kirchhoff (in Mitt. Bot. Staats-
samml. München 11: 432. 1974) to commemorate Victoria A. Matthews, is to be corrected
to A. matthewsiae Podlech & Kirchhoff; it is not therefore a later homonym of A. mat-
thewsii
S. Watson (1883) (see Agerer-Kirchhoff & Podlech in Mitt. Bot. Staatssamml.
München 12: 375. 1976).

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60-60B Orthography

Ex. 25.  Codium “geppii” (Schmidt in Biblioth. Bot. 91: 50. 1923), which commemorates
“A. & E. S. Gepp”, is to be corrected to C. geppiorum O. C. Schmidt.

60.12.  Epithets of fungus names derived from the generic name of an
associated organism are to be spelled in accordance with the accepted
spelling of that organism’s name; other spellings are regarded as ortho-
graphical variants to be corrected (see Art. 61).

Ex. 26.  Phyllachora “anonicola” (Chardon in Mycologia 32: 190. 1940) is to be altered to
P. annonicola Chardon, since the spelling Annona is now accepted in preference to
“Anona”. – Meliola “albizziae” (Hansford & Deighton in Mycol. Pap. 23: 26. 1948) is to
be altered to M. albiziae Hansf. & Deighton, since the spelling Albizia is now accepted in
preference to “Albizzia”.

Recommendation 60A

60A.1.  When a new name or its epithet is to be derived from Greek, the translit-
eration to Latin should conform to classical usage.

60A.2.  The spiritus asper should be transcribed in Latin as the letter h.

Recommendation 60B

60B.1.  When a new generic name, or subgeneric or sectional epithet, is taken
from the name of a person, it should be formed as follows:

(a)  When the name of the person ends with a vowel, the letter -a is added (thus
        Ottoa after Otto; Sloanea after Sloane), except when the name ends with -a,
        when -ea is added (e.g. Collaea after Colla), or with -ea (as Correa), when
        no letter is added.

(b)  When the name of the person ends with a consonant, the letters -ia are added,
        but when the name ends with -er, either of the terminations -ia and -a is ap-
        propriate (e.g. Sesleria after Sesler and Kernera after Kerner).

(c)   In latinized personal names ending with -us this termination is dropped (e.g. Dil-
        lenia after Dillenius) before applying the procedure described under (a) and (b).

Note 1.  The syllables not modified by these endings retain their original spelling
(Art. 60.1), unless they contain letters foreign to Latin plant names or diacritical
signs (see Art. 60.6).

Note 2.  Names may be accompanied by a prefix or a suffix, or be modified by
anagram or abbreviation. In these cases they count as different words from the
original name.

Ex. 1.  Durvillaea Bory (1826) and Urvillea Kunth (1821); Lapeirousia Pourr. (1788) and
Peyrousea DC. (1838); Engleria O. Hoffm. (1888), Englerastrum Briq. (1894), and Eng-
lerella
Pierre (1891); Bouchea Cham. (1832) and Ubochea Baill. (1891); Gerardia L.
(1753) and Graderia Benth. (1846); Martia Spreng. (1818) and Martiusia Schult. &
Schult. f. (1822).

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Orthography 60C

Recommendation 60C

60C.1.  Personal names may be given Latin terminations and used to form spe-
cific and infraspecific epithets as follows (but see Rec. 60C.2):

(a)  If the personal name ends with a vowel or -er, substantival epithets are
        formed by adding the genitive inflection appropriate to the sex and number of
        the person(s) honoured (e.g., scopoli-i for Scopoli (m), fedtschenko-i for
        Fedtschenko (m), fedtschenko-ae for Fedtschenko (f), glaziou-i for Glaziou
        (m), lace-ae for Lace (f), gray-i for Gray (m), hooker-orum for the Hookers
        (m), except when the name ends with -a, in which case adding -e (singular)
        or -rum (plural) is appropriate (e.g. triana-e for Triana (m), pojarkova-e for
        Pojarkova (f), orlovskaja-e for Orlovskaja (f)).

(b)  If the personal name ends with a consonant (except -er), substantival epithets
        are formed by adding -i- (stem augmentation) plus the genitive inflection appro-
        priate to the sex and number of the person(s) honoured (e.g. lecard-ii for Le-
        card (m), wilson-iae for Wilson (f), verlot-iorum for the Verlot brothers, braun-
        iarum for the Braun sisters, mason-iorum for Mason, father and daughter).

(c)  If the personal name ends with a vowel, adjectival epithets are formed by
        adding -an- plus the nominative singular inflection appropriate to the gender
        of the generic name (e.g., Cyperus heyne-anus for Heyne, Vanda lindley-ana
        for Lindley, Aspidium bertero-anum for Bertero), except when the personal
        name ends with -a in which case -n- plus the appropriate inflection is added
        (e.g. balansa-nus (m), balansa-na (f), and balansa-num (n) for Balansa).

(d)  If the personal name ends with a consonant, adjectival epithets are formed by
        adding -i- (stem augmentation) plus -an- (stem of adjectival suffix) plus the
        nominative singular inflection appropriate to the gender of the generic name
        (e.g. Rosa webb-iana for Webb, Desmodium griffith-ianum for Griffith, Ver-
        bena hassler-iana for Hassler).

Note 1.  The hyphens in the above examples are used only to set off the total
appropriate termination.

60C.2.  Personal names already in Greek or Latin, or possessing a well-estab-
lished latinized form, should be given their appropriate Latin genitive to form
substantival epithets (e.g. alexandri from Alexander or Alexandre, augusti from
Augustus or August or Auguste, martini from Martinus or Martin, linnaei from
Linnaeus, martii from Martius, wislizeni from Wislizenus, edithae from Editha or
Edith, elisabethae from Elisabetha or Elisabeth, murielae from Muriela or Muriel,
conceptionis from Conceptio or Concepción, beatricis from Beatrix or Béatrice,
hectoris from Hector; but not “cami” from Edmond Camus or Aimée Camus).
Treating modern family names as if they were in third declension should be
avoided (e.g. munronis from Munro, richardsonis from Richardson).

60C.3.  In forming new epithets based on personal names the customary spelling
of the personal name should not be modified unless it contains letters foreign to
Latin plant names or diacritical signs (see Art. 60.4 and 60.6).

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60C-60F Orthography

60C.4.  Prefixes and particles ought to be treated as follows:

(a)   The Scottish patronymic prefix “Mac”, “Mc” or “M”, meaning “son of”,
        should be spelled “mac” and united with the rest of the name (e.g. macfady-
        enii after Macfadyen, macgillivrayi after MacGillivray, macnabii after McNab,
        mackenii after M’Ken).

(b)   The Irish patronymic prefix “O” should be united with the rest of the name or
        omitted (e.g. obrienii, brienianus after O’Brien, okellyi after O’Kelly).

(c)   A prefix consisting of an article (e.g. le, la, l’, les, el, il, lo), or containing an
        article (e.g. du, de la, des, del, della), should be united to the name (e.g. le-
        clercii after Le Clerc, dubuyssonii after DuBuysson, lafarinae after La Fa-
        rina, logatoi after Lo Gato).

(d)   A prefix to a family name indicating ennoblement or canonization should be
        omitted (e.g. candollei after de Candolle, jussieui after de Jussieu, hilairei
        after Saint-Hilaire, remyi after St. Rémy); in geographical epithets, however,
        “St.” is rendered as sanctus (m) or sancta (f) (e.g. sancti-johannis, of St. John,
        sanctae-helenae, of St. Helena).

(e)   A German or Dutch prefix should be omitted (e.g. iheringii after von Ihering,
        martii after von Martius, steenisii after van Steenis, strassenii after zu Stras-
        sen, vechtii after van der Vecht), but when it is normally treated as part of the
        family name it should be included in the epithet (e.g. vonhausenii after Von-
        hausen, vanderhoekii after Vanderhoek, vanbruntiae after Van Brunt).

Recommendation 60D

60D.1.  An epithet derived from a geographical name is preferably an adjective
and usually takes the termination -ensis, -(a)nus, -inus, or -icus.

Ex. 1.  Rubus quebecensis L. H. Bailey (from Quebec), Ostrya virginiana (Mill.) K. Koch
(from Virginia), Eryngium amorginum Rech. f. (from Amorgos), Fraxinus pennsylvanica
Marsh. (from Pennsylvania).

Recommendation 60E

60E.1.  The epithet in a new name should be written in conformity with the cus-
tomary spelling of the word or words from which it is derived and in accordance
with the accepted usage of Latin and latinization (see also Art. 23.5).

Ex. 1.  sinensis (not chinensis).

Recommendation 60F

60F.1.  All specific and infraspecific epithets should be written with an initial
lower-case letter, although authors desiring to use initial capital letters may do so
when the epithets are directly derived from the names of persons (whether actual or
mythical), or are vernacular (or non-Latin) names, or are former generic names.

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Orthography 60G-H

Recommendation 60G

60G.1.  A compound name or an epithet which combines elements derived from
two or more Greek or Latin words should be formed, as far as practicable, in
accordance with classical usage. This may be stated as follows (see also Note 1):

(a)   In a regular compound, a noun or adjective in non-final position appears as a
        compounding form generally obtained by

        (1)   removing the case ending of the genitive singular (Latin -ae, -i, -us, -is;
               Greek -os, -es, -as, -ous and the latter’s equivalent -eos) and

        (2)   before a consonant, adding a connecting vowel (-i- for Latin elements, -o-
                for Greek elements).

        (3)   Exceptions are common, and one should review earlier usages of a par-
                ticular compounding form.

(b)   In a pseudocompound, a noun or adjective in a non-final position appears as a
        word with a case ending, not as a modified stem. Examples are: nidus-avis
        (nest of bird), Myos-otis (ear of mouse), albo-marginatus (margined with
        white), etc. In epithets where tingeing is expressed, the modifying initial col-
        our often is in the ablative because the preposition e, ex, is implicit, e.g.,
        atropurpureus (blackish purple) from ex atro purpureus (purple tinged with
        black). Others have been deliberately introduced to reveal etymological dif-
        ferences when different word elements have the same compounding forms,
        such as tubi- from tube (tubus, tubi) or from trumpet (tuba, tubae) where tu-
        baeflorus can only mean trumpet-flowered; also carici- is the compounding
        form from both papaya (carica, caricae) and sedge (carex, caricis) where
        caricaefolius can only mean papaya-leaved. The latter use of the genitive
        singular of the first declension for pseudocompounding is treated as an error
        to be corrected unless it makes an etymological distinction (see Art. 60.8).

Note 1.  In forming some other apparently irregular compounds, classical usage is
commonly followed.

Ex. 1.  The compounding forms hydro- and hydr- (Hydro-phyllum) stem from water (hy-
dor,
hydatos);
calli- (Calli-stemon) derive from the adjective beautiful (kalos); and meli-
(Meli-osma, Meli-lotus) stem from honey (mel, melitos).

Note 2.  The hyphens in the above examples are given solely for explanatory
reasons. For the use of hyphens in generic names and in epithets see Art. 20.3,
23.1, and 60.9.

Recommendation 60H

60H.1.  The etymology of new names or of epithets in new names should be
given, especially when their meaning is not obvious.

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61-62 Variants – Gender

Article 61

61.1.  Only one orthographical variant of any one name is treated as val-
idly published: the form that appears in the original publication, except as
provided in Art. 60 (typographical or orthographical errors and standardi-
zations), Art. 14.11 (conserved spellings), and Art. 32.5 (incorrect Latin
terminations).

61.2.  For the purpose of this Code, orthographical variants are the various
spelling, compounding, and inflectional forms of a name or its epithet
(including typographical errors), only one nomenclatural type being in-
volved.

61.3.  If orthographical variants of a name appear in the original publica-
tion, the one that conforms to the rules and best suits the recommendations
of Art. 60 is to be retained; otherwise the first author who, in an effective-
ly published text (Art. 29-31), explicitly adopts one of the variants and
rejects the other(s) must be followed.

61.4.  The orthographical variants of a name are to be corrected to the
validly published form of that name. Whenever such a variant appears in
print, it is to be treated as if it were printed in its corrected form.

Note 1.  In full citations it is desirable that the original form of a corrected ortho-
graphical variant of a name be added (Rec. 50F).

61.5.  Confusingly similar names based on the same type are treated as
orthographical variants. (For confusingly similar names based on different
types, see Art. 53.3-5.)

Ex. 1.  Geaster (Fries, 1829) and Geastrum Pers. (1794) : Pers. (1801) are similar names
with the same type (see Taxon 33: 498. 1984); they are treated as orthographical variants
despite the fact that they are derived from two different nouns, aster (asteris) and astrum
(astri).

SECTION 2. GENDER

Article 62

62.1.  A generic name retains the gender assigned by botanical tradition,
irrespective of classical usage or the author’s original usage. A generic name
without a botanical tradition retains the gender assigned by its author.

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Gender 62

Note 1.  Botanical tradition usually maintains the classical gender of a Greek or
Latin word, when this was well established.

*Ex. 1.  In accordance with botanical tradition, Adonis L., Atriplex L., Diospyros L., He-
merocallis
L., Orchis L., Stachys L., and Strychnos L. must be treated as feminine while
Lotus L. and Melilotus Mill. must be treated as masculine. Eucalyptus L’Hér., which lacks
a botanical tradition, retains the feminine gender assigned by its author. Although their
ending suggests masculine gender, Cedrus Trew and Fagus L., like most other classical
tree names, were traditionally treated as feminine and thus retain that gender; similarly,
Rhamnus L. is feminine, despite the fact that Linnaeus assigned it masculine gender. Phy-
teuma
L. (n), Sicyos L. (m), and Erigeron L. (m) are other names for which botanical tradi-
tion has reestablished the classical gender despite another choice by Linnaeus.

62.2.  Compound generic names take the gender of the last word in the
nominative case in the compound. If the termination is altered, however,
the gender is altered accordingly.

Ex. 2.  Irrespective of the fact that Parasitaxus de Laub. (1972) was treated as masculine
when published, its gender is feminine: it is a compound of which the last part coincides
with the generic name Taxus L., which is feminine by botanical tradition (Art. 62.1).

Ex. 3.  Compound generic names in which the termination of the last word is altered:
Stenocarpus R. Br., Dipterocarpus C. F. Gaertn., and all other compounds ending in the
Greek masculine -carpos (or -carpus), e.g. Hymenocarpos Savi, are masculine; those in
-carpa or -carpaea, however, are feminine, e.g. Callicarpa L. and Polycarpaea Lam.; and
those in -carpon, -carpum, or -carpium are neuter, e.g. Polycarpon L., Ormocarpum
P. Beauv., and Pisocarpium Link.

(a)  Compounds ending in -codon, -myces, -odon, -panax, -pogon, -ste-
       mon, and other masculine words, are masculine.

Ex. 4.  Irrespective of the fact that the generic names Andropogon L. and Oplopanax (Torr.
& A. Gray) Miq. were originally treated as neuter by their authors, they are masculine.

(b)  Compounds ending in -achne, -chlamys, -daphne, -glochin, -mecon,
      -osma (the modern transcription of the feminine Greek word osmê),
      and other feminine words, are feminine. An exception is made in the
      case of names ending in -gaster, which strictly speaking ought to be
      feminine, but which are treated as masculine in accordance with bo-
      tanical tradition.

Ex. 5.  Irrespective of the fact that Tetraglochin Poepp., Triglochin L., Dendromecon
Benth., and Hesperomecon Greene were originally treated as neuter, they are feminine.

(c)  Compounds ending in -ceras, -dendron, -nema, -stigma, -stoma, and
      other neuter words, are neuter. An exception is made for names end-
      ing in -anthos (or -anthus), -chilos (-chilus or -cheilos), and -phykos
      (-phycos or -phycus), which ought to be neuter, since that is the gender
      of the Greek words anthos, cheilos, and phykos, but are treated as
      masculine in accordance with botanical tradition.

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62-62A Gender

Ex. 6.  Irrespective of the fact that Aceras R. Br. and Xanthoceras Bunge were treated as
feminine when first published, they are neuter.

62.3.  Arbitrarily formed generic names or vernacular names or adjectives
used as generic names, of which the gender is not apparent, take the gen-
der assigned to them by their authors. If the original author failed to indi-
cate the gender, the next subsequent author may choose a gender, and that
choice, if effectively published (Art. 29-31), is to be accepted.

Ex. 7.  Taonabo Aubl. (1775) is feminine because Aublet’s two species were T. dentata
and T. punctata.

Ex. 8.  Agati Adans. (1763) was published without indication of gender; feminine gender
was assigned to it by Desvaux (in J. Bot. Agric. 1: 120. 1813), who was the first subse-
quent author to adopt the name in an effectively published text, and his choice is to be
accepted.

Ex. 9.  The original gender of Manihot Mill. (1754), as apparent from some of the species
polynomials, was feminine, and Manihot is therefore to be treated as feminine.

62.4.  Generic names ending in -anthes, -oides or -odes are treated as
feminine and those ending in -ites as masculine, irrespective of the gender
assigned to them by the original author.

Recommendation 62A

62A.1.  When a genus is divided into two or more genera, the gender of the new
generic name or names should be that of the generic name that is retained.

Ex. 1.  When Boletus L. : Fr. is divided, the gender of the new generic names should be
masculine: Xerocomus Quél. (1887), Boletellus Murrill (1909), etc.

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

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Governance of the Code Div.III.1-Div.III.2

 
 
 
 

DIVISION III. PROVISIONS FOR THE GOVERNANCE OF

THE CODE
 

Div.III.1.  The Code may be modified only by action of a plenary session
of an International Botanical Congress on a resolution moved by the No-
menclature Section of that Congress ¹.

Div.III.2.  Permanent Nomenclature Committees are established under the
auspices of the International Association for Plant Taxonomy. Members
of these Committees are elected by an International Botanical Congress.
The Committees have power to co-opt and to establish subcommittees;
such officers as may be desired are elected.

(1)  General Committee, composed of the secretaries of the other Com-
       mittees, the rapporteur-général, the president and the secretary of the
       International Association for Plant Taxonomy, and at least 5 members
       to be appointed by the Nomenclature Section. The rapporteur-général
       is charged with the presentation of nomenclature proposals to the In-
       ternational Botanical Congress.

(2)  Committee for Spermatophyta.

(3)  Committee for Pteridophyta.

(4)  Committee for Bryophyta.

(5)  Committee for Fungi.

(6)  Committee for Algae.

(7)  Committee for Fossil Plants.

(8)  Editorial Committee, charged with the preparation and publication of
       the Code in conformity with the decisions adopted by the International
       Botanical Congress. Chairman: the rapporteur-général of the previous
       Congress, who is charged with the general duties in connection with
       the editing of the Code.

———————————————————————

¹ In the event that there should not be another International Botanical Congress, authority
  for the International code of botanical nomenclature shall be transferred to the Inter-
  national Union of Biological Sciences or to an organization at that time corresponding to
  it. The General Committee is empowered to define the machinery to achieve this.

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Div.III.3-Div.III.4 Governance of the Code

Div.III.3.  The Bureau of Nomenclature of the International Botanical
Congress. Its officers are: (1) the president of the Nomenclature Section,
elected by the organizing committee of the International Botanical Con-
gress in question; (2) the recorder, appointed by the same organizing com-
mittee; (3) the rapporteur-général, elected by the previous Congress; (4)
the vice-rapporteur, elected by the organizing committee on the proposal
of the rapporteur-général.

Div.III.4.  The voting on nomenclature proposals is of two kinds: (a) a
preliminary guiding mail vote and (b) a final and binding vote at the No-
menclature Section of the International Botanical Congress.

Qualifications for voting:

(a)  Preliminary mail vote:

       (1)  The members of the International Association for Plant Taxonomy.

       (2)  The authors of proposals.

       (3)  The members of the Permanent Nomenclature Committees.

Note 1.  No accumulation or transfer of personal votes is permissible.

(b)  Final vote at the sessions of the Nomenclature Section:

       (1)  All officially enrolled members of the Section. No accumulation
              or transfer of personal votes is permissible.

       (2)  Official delegates or vice-delegates of the institutes appearing on a
              list drawn up by the Bureau of Nomenclature of the International
              Botanical Congress and submitted to the General Committee for
              final approval; such institutes are entitled to 1-7 votes, as specified
              on the list. No single institution, even in the wide sense of the
              term, is entitled to more than 7 votes. Transfer of institutional
              votes to specified vice-delegates is permissible, but no single per-
              son will be allowed more than 15 votes, personal vote included.
              Institutional votes may be deposited at the Bureau of Nomencla-
              ture to be counted in a specified way for specified proposals.

 
 
 
 
 
 
 

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Hybrids H.1-H.3

 
 
 
 

APPENDIX I
 

NAMES OF HYBRIDS

Article H.1

H.1.1.  Hybridity is indicated by the use of the multiplication sign × or by the
addition of the prefix “notho-” ¹ to the term denoting the rank of the taxon.

Article H.2

H.2.1.  A hybrid between named taxa may be indicated by placing the
multiplication sign between the names of the taxa; the whole expression is
then called a hybrid formula.

Ex. 1.  Agrostis L. × Polypogon Desf.; Agrostis stolonifera L. × Polypogon monspeliensis
(L.) Desf.; Salix aurita L. × S. caprea L.; Mentha aquatica L. × M. arvensis L. × M. spi-
cata
L.; Polypodium vulgare subsp. prionodes (Asch.) Rothm. × subsp. vulgare; Tilletia
caries
(Bjerk.) Tul. × T. foetida (Wallr.) Liro
.

Recommendation H.2A

H.2A.1.  It is usually preferable to place the names or epithets in a formula in al-
phabetical order. The direction of a cross may be indicated by including the sexual
symbols (♀: female; ♂: male) in the formula, or by placing the female parent first.
If a non-alphabetical sequence is used, its basis should be clearly indicated.

Article H.3

H.3.1.  Hybrids between representatives of two or more taxa may receive
a name. For nomenclatural purposes, the hybrid nature of a taxon is indi-
cated by placing the multiplication sign × before the name of an intergen-
eric hybrid or before the epithet in the name of an interspecific hybrid, or

———————————————————————

¹ From the Greek nothos, meaning hybrid.

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H.3-H.4 Hybrids

by prefixing the term “notho-” (optionally abbreviated “n-”) to the term
denoting the rank of the taxon (see Art. 3.2 and 4.4). All such taxa are
designated nothotaxa.

Ex. 1.  (The putative or known parentage is found in Art. H.2 Ex. 1.) ×Agropogon
P. Fourn. (1934); ×Agropogon littoralis (Sm.) C. E. Hubb. (1946); Salix ×capreola An-
dersson (1867); Mentha ×smithiana R. A. Graham (1949); Polypodium vulgare notho-
subsp. mantoniae (Rothm.) Schidlay (in Futák, Fl. Slov. 2: 225. 1966).

H.3.2.  A nothotaxon cannot be designated unless at least one parental
taxon is known or can be postulated.

H.3.3.  For purposes of homonymy and synonymy the multiplication sign
and the prefix “notho-” are disregarded.

Ex. 2.  ×Hordelymus Bachteev & Darevsk. (1950) (= Elymus L. × Hordeum L.) is a later
homonym of Hordelymus (K. Jess.) K. Jess. (1885).

Note 1.  Taxa which are believed to be of hybrid origin need not be designated as
nothotaxa.

Ex. 3.  The true-breeding tetraploid raised from the artificial cross Digitalis grandiflora L.
× D. purpurea L. may, if desired, be referred to as D. mertonensis B. H. Buxton & C.
D. Darl. (1931); Triticum aestivum L. (1753) is treated as a species although it is not found
in nature and its genome has been shown to be composed of those of T. dicoccoides
Körn.) Körn., T. speltoides (Tausch) Gren. ex K. Richt., and T. tauschii (Coss.) Schmalh.;
the taxon known as Phlox divaricata subsp. laphamii (A. W. Wood) Wherry (in Morris
Arbor. Monogr. 3: 41. 1955) is believed by Levin (in Evolution 21: 92-108. 1967) to be a
stabilized product of hybridization between P. divaricata L. subsp. divaricata and P. pilosa
subsp. ozarkana Wherry; Rosa canina L. (1753), a polyploid believed to be of ancient
hybrid origin, is treated as a species.

Recommendation H.3A

H.3A.1.  The multiplication sign in the name of a nothotaxon should be placed
against the initial letter of the name or epithet. However, if the mathematical
symbol is not available and the letter “x” is used instead, a single letter space may
be left between it and the epithet if this helps to avoid ambiguity. The letter “x”
should be in lower case.

Article H.4

H.4.1.  When all the parent taxa can be postulated or are known, a notho-
taxon is circumscribed so as to include all individuals (as far as they can
be recognized) derived from the crossing of representatives of the stated
parent taxa (i.e. not only the but subsequent filial generations and also
back-crosses and combinations of these). There can thus be only one

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Hybrids H.4-H.5A

correct name corresponding to a particular hybrid formula; this is the ear-
liest legitimate name (see Art. 6.3) in the appropriate rank (Art. H.5), and
other names to which the same hybrid formula applies are synonyms of it.

Ex. 1.  The names Oenothera ×wienii Renner ex Rostański (1977) and O. ×drawertii Ren-
ner ex Rostański (1966) are both considered to apply to the hybrid O. biennis L. × O. vil-
losa
Thunb. subsp. villosa; the types of the two nothospecific names are known to differ
by a whole gene complex; nevertheless, the later name is treated as a synonym of the
earlier.

Note 1.  Variation within nothospecies and nothotaxa of lower rank may be treated
according to Art. H.12 or, if appropriate, according to the International code of
nomenclature for cultivated plants
.

Article H.5

H.5.1.  The appropriate rank of a nothotaxon is that of the postulated or
known parent taxa.

H.5.2.  If the postulated or known parent taxa are of unequal rank the ap-
propriate rank of the nothotaxon is the lowest of these ranks.

Note 1.  When a taxon is designated by a name in a rank inappropriate to its hy-
brid formula, the name is incorrect in relation to that hybrid formula but may
nevertheless be correct, or may become correct later (see also Art. 52 Note 3).

Ex. 1.  The combination Elymus ×laxus (Fr.) Melderis & D. C. McClint. (1983), based on
Triticum laxum Fr. (1842), was published for hybrids with the formula E. farctus subsp.
boreoatlanticus (Simonet & Guin.) Melderis × E. repens (L.) Gould, so that the combina-
tion is in a rank inappropriate to the hybrid formula. It is, however, the correct name appli-
cable to all hybrids between E. farctus (Viv.) Melderis and E. repens.

Ex. 2.  Radcliffe-Smith incorrectly published the nothospecific name Euphorbia ×cornu-
biensis
Radcl.-Sm. (1985) for E. amygdaloides L. × E. characias subsp. wulfenii (W. D.
J. Koch) Radcl.-Sm., although the correct designation for hybrids between E. amygdaloi-
des
and E. characias L. is E. ×martini Rouy (1900); later, he remedied his mistake by
publishing the combination E. ×martini nothosubsp. cornubiensis (Radcl.-Sm.) Radcl.-Sm.
(in Taxon 35: 349. 1986). However, the name E. ×cornubiensis is potentially correct for
hybrids with the formula E. amygdaloides × E. wulfenii W. D. J. Koch.

Recommendation H.5A

H.5A.1.  When publishing a name of a new nothotaxon at the rank of species or
below, authors should provide any available information on the taxonomic iden-
tity, at lower ranks, of the known or postulated parent plants of the type of the
name.

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H.6 Hybrids

Article H.6

H.6.1.  A nothogeneric name (i.e. the name at generic rank for a hybrid
between representatives of two or more genera) is a condensed formula or
is equivalent to a condensed formula.

H.6.2.  The nothogeneric name of a bigeneric hybrid is a condensed for-
mula in which the names adopted for the parental genera are combined
into a single word, using the first part or the whole of one, the last part or
the whole of the other (but not the whole of both) and, optionally, a con-
necting vowel.

Ex. 1.  ×Agropogon P. Fourn. (1934) (= Agrostis L. × Polypogon Desf.); ×Gymnana-
camptis
Asch. & Graebn. (1907) (= Anacamptis Rich. × Gymnadenia R. Br.); ×Cupresso-
cyparis
Dallim. (1938) (= Chamaecyparis Spach × Cupressus L.); ×Seleniphyllum G.
D. Rowley (1962) (= Epiphyllum Haw. × Selenicereus (A. Berger) Britton & Rose).

Ex. 2.  ×Amarcrinum Coutts (1925) is correct for Amaryllis L. × Crinum L., not “×Crin-
donna
”. The latter formula was proposed by Ragionieri (1921) for the same nothogenus,
but was formed from the generic name adopted for one parent (Crinum) and a synonym
(Belladonna Sweet) of the generic name adopted for the other (Amaryllis). Being contrary
to Art. H.6, it is not validly published under Art. 32.1(b).

Ex. 3.  The name ×Leucadenia Schltr. (1919) is correct for Leucorchis E. Mey. × Gymn-
adenia
R. Br., but if the generic name Pseudorchis Ség. is adopted instead of Leucorchis,
×Pseudadenia P. F. Hunt (1971) is correct.

Ex. 4.  Boivin (1967) published ×Maltea for what he considered to be the intergeneric
hybrid Phippsia (Trin.) R. Br. × Puccinellia Parl. As this is not a condensed formula, the
name cannot be used for that intergeneric hybrid, for which the correct name is ×Puc-
ciphippsia
Tzvelev (1971). Boivin did, however, provide a Latin description and designate
a type; consequently, Maltea B. Boivin is a validly published generic name and is correct
if its type is treated as belonging to a separate genus, not to a nothogenus.

H.6.3.  The nothogeneric name of an intergeneric hybrid derived from
four or more genera is formed from the name of a person to which is
added the termination -ara; no such name may exceed eight syllables.
Such a name is regarded as a condensed formula.

Ex. 5.  ×Beallara Moir (1970) (= Brassia R. Br. × Cochlioda Lindl. × Miltonia Lindl. ×
Odontoglossum Kunth).

H.6.4.  The nothogeneric name of a trigeneric hybrid is either (a) a con-
densed formula in which the three names adopted for the parental genera
are combined into a single word not exceeding eight syllables, using the
whole or first part of one, followed by the whole or any part of another,
followed by the whole or last part of the third (but not the whole of all
three) and, optionally, one or two connecting vowels, or (b) a name
formed like that of a nothogenus derived from four or more genera, i.e.,
from a personal name to which is added the termination -ara.

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Hybrids H.6-H.8

Ex. 6.  ×Sophrolaeliocattleya Hurst (1898) (= Cattleya Lindl. × Laelia Lindl. × Sophronitis
Lindl.); ×Vascostylis Takakura (1964) (= Ascocentrum Schltr. ex J. J. Sm. × Rhynchostylis
Blume × Vanda W. Jones ex R. Br.); ×Rodrettiopsis Moir (1976) (= Comparettia Poepp. &
Endl. × Ionopsis Kunth × Rodriguezia Ruiz & Pav.); ×Devereuxara Kirsch (1970) (=
Ascocentrum Schltr. ex J. J. Sm. × Phalaenopsis Blume × Vanda W. Jones ex R. Br.).

Recommendation H.6A

H.6A.1.  When a nothogeneric name is formed from the name of a person by
adding the termination -ara, that person should preferably be a collector, grower,
or student of the group.

Article H.7

H.7.1.  The name of a nothotaxon which is a hybrid between subdivisions
of a genus is a combination of an epithet, which is a condensed formula
formed in the same way as a nothogeneric name (Art. H.6.2), with the
name of the genus.

Ex. 1.  Ptilostemon nothosect. Platon Greuter (in Boissiera 22: 159. 1973), comprising
hybrids between P. sect. Platyrhaphium Greuter and P. sect. Ptilostemon; P. nothosect.
Plinia Greuter (in Boissiera 22: 158. 1973), comprising hybrids between P. sect. Platyrha-
phium
and P. sect. Cassinia Greuter.

Article H.8

H.8.1.  When the name or the epithet in the name of a nothotaxon is a
condensed formula (Art. H.6 and H.7), the parental names used in its for-
mation must be those which are correct for the particular circumscription,
position, and rank accepted for the parental taxa.

Ex. 1.  If the genus Triticum L. is interpreted on taxonomic grounds as including Triticum (s. str.)
and Agropyron Gaertn., and the genus Hordeum L. as including Hordeum (s. str.) and
Elymus L., then hybrids between Agropyron and Elymus as well as between Triticum (s. str.)
and Hordeum (s. str.) are placed in the same nothogenus, ×Tritordeum Asch. & Graebn.
(1902). If, however, Agropyron is separated generically from Triticum, hybrids between Agro-
pyron
and Hordeum (s. str. or s. lat.) are placed in the nothogenus ×Agrohordeum A. Camus
(1927). Similarly, if Elymus is separated generically from Hordeum, hybrids between Elymus
and Triticum (s. str. or s. lat.) are placed in the nothogenus ×Elymotriticum P. Fourn. (1935).
If both Agropyron and Elymus are given generic rank, hybrids between them are placed in
the nothogenus ×Agroelymus A. Camus (1927); ×Tritordeum is then restricted to hybrids
between Hordeum (s. str.) and Triticum (s. str.), and hybrids between Elymus and Hor-
deum
are placed in ×Elyhordeum Mansf. ex Tsitsin & Petrova (1955), a substitute name for
×Hordelymus Bachteev & Darevsk. (1950) non Hordelymus (K. Jess.) K. Jess. (1885).

H.8.2.  Names ending in -ara for nothogenera, which are equivalent to
condensed formulae (Art. H.6.3-4), are applicable only to plants which are
accepted taxonomically as derived from the parents named.

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H.8-H.10 Hybrids

Ex. 2.  If Euanthe Schltr. is recognized as a distinct genus, hybrids simultaneously involv-
ing its only species, E. sanderiana (Rchb.) Schltr., and the three genera Arachnis Blume,
Renanthera Lour., and Vanda W. Jones ex R. Br. must be placed in ×Cogniauxara Garay
& H. R. Sweet (1966); if, on the other hand, E. sanderiana is included in Vanda, the same
hybrids are placed in ×Holttumara Holttum (1958) (Arachnis × Renanthera × Vanda).

Article H.9

H.9.1.  In order to be validly published, the name of a nothogenus or of a
nothotaxon with the rank of subdivision of a genus (Art. H.6 and H.7)
must be effectively published (see Art. 29-31) with a statement of the
names of the parent genera or subdivisions of genera, but no description
or diagnosis is necessary, whether in Latin or in any other language.

Ex. 1.  Validly published names: ×Philageria Mast. (1872), published with a statement of
parentage, Lapageria Ruiz & Pav. × Philesia Comm. ex Juss.; Eryngium nothosect. Alpestria
Burdet & Miège, pro sect. (in Candollea 23: 116. 1968), published with a statement of its
parentage, E. sect. Alpina H. Wolff × E. sect. Campestria H. Wolff; ×Agrohordeum A. Ca-
mus (1927) (= Agropyron Gaertn. × Hordeum L.), of which ×Hordeopyron Simonet (1935,
“Hordeopyrum”) is a later synonym.

Note 1.  Since the names of nothogenera and nothotaxa with the rank of a subdi-
vision of a genus are condensed formulae or treated as such, they do not have types.

Ex. 2.  The name ×Ericalluna Krüssm. (1960) was published for plants (“×E. bealeana”,
nom. inval.
) which were thought to be the product of the cross Calluna vulgaris (L.) Hull ×
Erica cinerea L. If it is considered that these are not hybrids, but are variants of E. cinerea,
the name ×Ericalluna Krüssm. remains available for use if and when known or postulated
plants of Calluna Salisb. × Erica L. should appear.

Ex. 3.  ×Arabidobrassica Gleba & Fr. Hoffm. (in Naturwissenschaften 66: 548. 1979), a
nothogeneric name which was validly published with a statement of parentage for the
result of somatic hybridization by protoplast fusion of Arabidopsis thaliana (L.) Heynh.
with Brassica campestris L., is also available for intergeneric hybrids resulting from nor-
mal crosses between Arabidopsis Heynh. and Brassica L., should any be produced.

Note 2.  However, names published merely in anticipation of the existence of a
hybrid are not validly published under Art. 34.1(b).

Article H.10

H.10.1.  Names of nothotaxa at the rank of species or below must conform
with the provisions (a) in the body of the Code applicable to the same
ranks and (b) in Art. H.3. Infringements of Art. H.3.1. are treated as errors
to be corrected.

Ex. 1.  The nothospecies name Melampsora ×columbiana G. Newc. (in Mycol. Res. 104:
271. 2000) was validly published, with a Latin description and designation of a holotype,
for the hybrid between M. medusae Thüm. and M. occidentalis H. S. Jacks.

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Hybrids H.10-H.10B

H.10.2.  Taxa previously published as species or infraspecific taxa which
are later considered to be nothotaxa may be indicated as such, without
change of rank, in conformity with Art. 3 and 4 and by the application of
Art. 50 (which also operates in the reverse direction).

H.10.3.  The following are considered to be formulae and not true epi-
thets: designations consisting of the epithets of the names of the parents
combined in unaltered form by a hyphen, or with only the termination of
one epithet changed, or consisting of the specific epithet of the name of
one parent combined with the generic name of the other (with or without
change of termination).

Ex. 2.  The designation Potentilla “atrosanguinea-pedata” published by Maund (in Bot.
Gard. 5: No. 385, t. 97. 1833) is considered to be a formula meaning Potentilla atrosan-
guinea
Lodd. ex D. Don × P. pedata Nestl.

Ex. 3.  Verbascum “nigro-lychnitis” (Schiede, Pl. Hybr.: 40. 1825) is considered to be a
formula, Verbascum lychnitis L. × V. nigrum L.; the correct binary name for this hybrid is
Verbascum ×schiedeanum W. D. J. Koch (1844).

Ex. 4.  The following names include true epithets (but see Rec. H.10A): Acaena
×anserovina Orchard (1969) (from A. anserinifolia (J. R. Forst. & G. Forst.) J. Armstr. and
A. ovina A. Cunn.); Micromeria ×benthamineolens Svent. (1969) (from M. benthamii
Webb & Berthel. and M. pineolens Svent.).

Note 1.  Since the name of a nothotaxon at the rank of species or below has a
type, statements of parentage play a secondary part in determining the application
of the name.

Ex. 5.  Quercus ×deamii Trel. (in Mem. Natl. Acad. Sci. 20: 14. 1924) when described was
considered as the cross Q. alba L. × Q. muehlenbergii Engelm. However, progeny grown
from acorns from the tree from which the type originated led Bartlett to conclude that the
parents were in fact Q. macrocarpa Michx. and Q. muehlenbergii. If this conclusion is
accepted, the name Q. ×deamii applies to Q. macrocarpa × Q. muehlenbergii, and not to
Q. alba × Q. muehlenbergii.

Recommendation H.10A

H.10A.1.  In forming epithets for names of nothotaxa at the rank of species and
below, authors should avoid combining parts of the epithets of the names of the
parents.

Recommendation H.10B

H.10B.1.  When contemplating the publication of new names for hybrids between
named infraspecific taxa, authors should carefully consider whether they are
really needed, bearing in mind that formulae, though more cumbersome, are more
informative.

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H.11-H.12 Hybrids

Article H.11

H.11.1.  The name of a nothospecies of which the postulated or known
parent species belong to different genera is a combination of a nothospeci-
fic epithet with a nothogeneric name.

Ex. 1.  ×Heucherella tiarelloides (Lemoine & E. Lemoine) H. R. Wehrh. is considered to
have originated from the cross between a garden hybrid of Heuchera L. and Tiarella cordi-
folia
L. (see Stearn in Bot. Mag. 165: ad t. 31. 1948). Its original name, Heuchera ×tiarel-
loides
Lemoine & E. Lemoine (1912), is therefore incorrect.

Ex. 2.  When Orchis fuchsii Druce was renamed Dactylorhiza fuchsii (Druce) Soó the
name for its hybrid with Coeloglossum viride (L.) Hartm., ×Orchicoeloglossum mixtum
Asch. & Graebn. (1907), became the basis of the necessary new combination ×Dactylo-
glossum mixtum
(Asch. & Graebn.) Rauschert (1969).

H.11.2.  The final epithet in the name of an infraspecific nothotaxon of
which the postulated or known parental taxa are assigned to different spe-
cies, may be placed subordinate to the name of a nothospecies (but see
Rec. H.10B).

Ex. 3.  Mentha ×piperita L. nothosubsp. piperita (= M. aquatica L. × M. spicata L. subsp.
spicata); Mentha ×piperita nothosubsp. pyramidalis (Ten.) Harley (in Kew Bull. 37: 604.
1983) (= M. aquatica L. × M. spicata subsp. tomentosa (Briq.) Harley).

Article H.12

H.12.1.  Subordinate taxa within nothospecies may be recognized without
an obligation to specify parent taxa at the subordinate rank. In this case
non-hybrid infraspecific categories of the appropriate rank are used.

Ex. 1.  Mentha ×piperita f. hirsuta Sole; Populus ×canadensis var. serotina (R. Hartig)
Rehder and P. ×canadensis var. marilandica (Poir.) Rehder (see also Art. H.4 Note 1).

Note 1.  As there is no statement of parentage at the rank concerned there is no
control of circumscription at this rank by parentage (compare Art. H.4).

Note 2.  It is not feasible to treat subdivisions of nothospecies by the methods of
both Art. H.10 and H.12.1 at the same rank.

H.12.2.  Names published at the rank of nothomorph¹ are treated as hav-
ing been published as names of varieties (see Art. 50).

 
 

———————————————————————

¹ Pre-Sydney editions of the Code permitted only one rank under provisions equivalent to
  H.12. That rank was equivalent to variety and the category was termed “nothomorph”.

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      [ Appendix II, listing conserved names of families, is not included here ]
 
 
 
 
 

   
      [ Appendix IIA, Nomina familiarum algarum, fungorum, pteridophytorum et
         fossilium conservanda et rejicienda
is not included here ]
 
 
 
 
 

   
      [ Appendix IIB, Nomina familiarum bryophytorum et spermatophytorum
         conservanda
, is not included here ]
 
 
 
 
 

   
      [ Appendix III, listing conserved names of genera and species, is not included here ]
 
 
 
 
 

   
      [ Appendix IIIA, Nomina generica conservanda et rejicienda, is not included here ]
 
 
 
 
 

   
      [ Appendix IIIB, Nomina specifica conservanda et rejicienda, is not included here ]
 
 
 
 
 

   
      [ Appendix IV, Nomina utique rejicienda, is not included here ]
 
 
 
 
 

   
      [ Appendix V, Opera utique oppressa, is not included here ]
 
 
 
 
 


 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

   
      [ Not present in this edition ]
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

   
             [ sic ]
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 

   
       [ supposed to be superscript ]