CHAPTER II

STATUS, TYPIFICATION, AND PRIORITY OF NAMES

SECTION 4

LIMITATION OF THE PRINCIPLE OF PRIORITY

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 and F.1, this Code provides, in App. II–IV, lists of names of families, genera, and species that are conserved (nomina conservanda) (see Rec. 50E.1). Conserved names are legitimate even though initially they may have been illegitimate. The name of a subdivision of a genus or of an infraspecific taxon may be conserved with a conserved type and listed in App. III and IV, respectively, when it is the basionym or replaced synonym of a name of a genus or species that could not continue to be used in its current sense without conservation.

14.2. Conservation aims at retention of those names that best serve stability of nomenclature.

14.3. The application of both conserved and rejected names is determined by nomenclatural types. The type of the species name cited as the type of a conserved generic name may, if desirable, be conserved and listed in App. IV. Application of conserved and rejected names of nothogenera is determined by a statement of parentage (Art. H.9.1).

14.4. A conserved name of a family or genus is conserved against all other names at the same rank with the same type (homotypic, i.e. nomenclatural, synonyms, which are to be rejected) whether or not these are cited in the corresponding list as rejected names, and against those names with different types (heterotypic, i.e. taxonomic, 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 rejected names.

[footnote]¹ The International Code of Zoological Nomenclature uses the terms “objective synonym” and “subjective synonym” for homotypic and heterotypic synonym, respectively.

Note 1. Except as by Art. 14.14 (see also Art. 14.9), the Code does not provide for conservation of a name against itself, i.e. against an “isonym” (Art. 6 Note 2: the same name with the same type but with a different place and date of valid publication and perhaps with a different author). Only the earliest known isonyms are listed in App. IIA, III, and IV.

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

Ex. 1. Rejection of Lycopersicon lycopersicum (L.) H. Karst. (Deut. Fl.: 966. 1882) in favour of L. esculentum Mill. (Gard. Dict., ed. 8: Lycopersicon No. 1. 1768) does not preclude the use of the homotypic Solanum lycopersicum L. (Sp. Pl.: 185. 1753).

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, except for the conserved family names listed in App. IIB, which are conserved against unlisted names.

Ex. 2. If Mahonia Nutt. (Gen. N. Amer. Pl. 1: 211. 1818) is united with Berberis L. (Sp. Pl.: 330. 1753), the combined genus will bear the prior name Berberis, although Mahonia is conserved and Berberis is not.

Ex. 3. Nasturtium W. T. Aiton (Hort. Kew., ed. 2, 4: 109. 1812) was conserved only against the homonym Nasturtium Mill. (Gard. Dict. Abr., ed. 4: Nasturtium. 1754) and the homotypic (nomenclatural) synonym Cardaminum Moench (Methodus: 262. 1794); consequently if reunited with Rorippa Scop. (Fl. Carniol.: 520. 1760) it must bear the name Rorippa.

Ex. 4. Combretaceae R. Br. (Prodr.: 351. 1810) is conserved against the unlisted earlier heterotypic name Terminaliaceae J. St.-Hil. (Expos. Fam. Nat. 1: 178. 1805).

14.6. When a name of a taxon has been conserved against an earlier heterotypic synonym, 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 conserved name.

Ex. 5. The generic name Luzuriaga Ruiz & Pav. (Fl. Peruv. 3: 65. 1802) is conserved against the earlier names Enargea Banks ex Gaertn. (Fruct. Sem. Pl. 1: 283. 1788) and Callixene Comm. ex Juss. (Gen. Pl.: 41. 1789). If, however, Enargea is considered to be a separate genus, the name Enargea is retained for it.

Ex. 6. To preserve the name Roystonea regia (Kunth) O. F. Cook (in Science, n.s., 12: 479. 1900), its basionym Oreodoxa regia Kunth (in Humboldt & al., Nov. Gen. Sp. 1, ed. qu.: 305; ed. fol.: 244. 1816) is conserved against Palma elata W. Bartram (Travels Carolina: iv, 115–116. 1791). However, the name R. elata (W. Bartram) F. Harper (in Proc. Biol. Soc. Washington 59: 29. 1946) can be used for a species distinct from R. regia.

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

Ex. 7. Enallagma (Miers) Baill. (Hist. Pl. 10: 54. 1888) is conserved against Dendrosicus Raf. (Sylva Tellur.: 80. 1838), but not against Amphitecna Miers (in Trans. Linn. Soc. London 26: 163. 1868); if Enallagma, Dendrosicus, 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 and spelling of a conserved name (evident misspellings excepted) may only be changed by the procedure outlined in Art. 14.12.

Ex. 8. 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 Botanical Congress (see App. III).

14.9. A name may be conserved with a different type from that designated by the author or determined by application of the Code (see also Art. 10.4). Such a name may be conserved either (a) from its place of valid publication (even though the type may not then have been included in the named taxon) or (b) from a later publication by an author who did include the type as conserved. In the second case the name as conserved is treated as validly published in the later publication, whether or not the name as conserved was accompanied by a description or diagnosis of the taxon named; the original name and the name as conserved are treated as homonyms (see Art. 14.10).

Ex. 9. Bromus sterilis L. (Sp. Pl.: 77. 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. 10. Protea L. (Sp. Pl.: 94. 1753) did not include the conserved type of the generic name, P. cynaroides (L.) L. (Mant. Pl.: 190. 1771), which in 1753 was placed in the genus Leucadendron. Protea was therefore conserved from the 1771 publication, and Protea L. (Mant. Pl.: 187. 1771), although not intended 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 not made illegitimate by that conservation but is unavailable for use; if not otherwise illegitimate, it may serve as basionym of another name or combination based on the same type (see also Art. 55.3).

Ex. 11. The generic name Smithia Aiton (Hort. Kew. 3: 496. 1789), conserved against Damapana Adans. (Fam. Pl. 2: 323, 548. 1763), is conserved automatically against the earlier, listed homonym Smithia Scop. (Intr. Hist. Nat.: 322. 1777). – Blumea DC. (in Arch. Bot. (Paris) 2: 514. 1833) is conserved automatically against Blumea Rchb. (Consp. Regn. Veg.: 209. 1828–1829), although the latter name is not listed alongside the former in App. III.

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 date to the author who validly published it, not to an author who later introduced the conserved spelling or gender.

Ex. 12. The spelling Rhodymenia, used by Montagne (in Ann. Sci. Nat., Bot., ser. 2, 12: 44. 1839), has been conserved against the original spelling ‘Rhodomenia’, used by Greville (Alg. Brit.: xlviii, 84. 1830). The name is cited as Rhodymenia Grev. (1830).

Note 3. The date upon which a name was conserved does not affect its priority (Art. 11), which is determined only on the basis of the date of its valid publication (Art. 32–45; see also Art. F.4, F.5.1, F.5.2, and H.9; but see Art. 14.9 and 14.14).

14.12. The lists of conserved names will remain permanently open for additions and changes. Any proposal of an additional name must be accompanied by a detailed statement of the cases both for and against conservation. Such proposals must be submitted to the General Committee, which will refer them for examination to the specialist committees for the various taxonomic groups (see Rec. 14A, Div. III Prov. 2.2, 7.9, and 7.10; see also Art. 34.1 and 56.2).

14.13. Entries of conserved names may not be deleted.

Ex. 13. In the Seattle Code of 1972 (p. 254), “Alternaria C. G. Nees ex Wallroth, Fl. Crypt. Germ. 148. 1833” was listed as conserved against “Macrosporium E. M. Fries, Syst. Mycol. 3: 373. 1832” because Macrosporium Fr. antedated Alternaria “C. G. Nees ex Wallroth” in relation to the then starting-point work for fungi (Fries, Systema mycologicum, vol. 1, 1 January 1821). Conservation became unnecessary following the abolition of later starting-point dates for fungi at the Sydney Congress of 1981 and in the Sydney Code of 1983, which resulted in Alternaria being recognized as having been validly published by Nees (Syst. Pilze: 72. 1816). In addition, it was realized that Alternaria had been adopted by Fries in the introduction to the sanctioning work (Syst. Mycol. 1: xlvi. 1821; Art. F.3.1). Because the entry cannot be deleted, Alternaria Nees : Fr. continues to be listed in App. III, but without a corresponding rejected name.

14.14. The places of publication cited for conserved names of families in App. IIB are treated as correct in all circumstances and consequently are not to be changed, except under the provisions of Art. 14.12, even when otherwise such a name would not be validly published or when it is a later isonym.

14.15. When a proposal for the conservation (Art. 14) or protection (Art. F.2) of a name has been approved by the General Committee after study by the specialist committee for the taxonomic group concerned, retention of that name as approved is authorized subject to the decision of a later International Botanical Congress (see also Art. 34.2 and 56.3). Before 1 January 1954, conservation takes effect on the date of decision by the relevant International Botanical Congress. On or after that date, conservation or protection takes effect on the date of effective publication (Art. 29–31) of the General Committee’s approval.

Note 4. The effective dates for International Botanical Congress (IBC) decisions on conservation of names made before 1954 are as follows:

(a) Conservation of names in the 1906 Vienna Rules became effective on 17 June 1905 at the II IBC in Vienna (see Verh. Int. Bot. Kongr. Wien 1905: 135–137. 1906).

(b) Conservation of names in the 1912 Brussels Rules became effective on 18 May 1910 at the III IBC in Brussels (see Actes Congr. Int. Bot. Bruxelles 1910: 67–83. 1912).

(c) Conservation of names in the 1952 Stockholm Code include: (1) those of the Special Committee for Phanerogamae and Pteridophyta, which became effective on 1 June 1940 under the authority of the VI IBC held in Amsterdam in 1935 (see Bull. Misc. Inform. Kew 1940: 81–134); (2) those of the Special Committee for Fungi, which became effective on 20 July 1950 at the VII IBC in Stockholm (see Regnum Veg. 1: 549–550. 1953).

The date, from 1954 onward, of the General Committee’s approval of a particular conservation or protection proposal can be determined by consulting the International Code of Nomenclature for algae, fungi, and plants Appendices database (http://botany.si.edu/references/codes/props/index.cfm).

Recommendation 14A

14A.1. When a proposal for the conservation (Art. 14) or protection (Art. F.2) of a name has been referred to the appropriate specialist committee for study, authors should follow existing usage of names as far as possible pending the General Committee’s recommendation on the proposal (see also Rec. 34A and 56A).