RULES AND RECOMMENDATIONS
TAXA AND THEIR RANKS
1.1. Taxonomic groups at any rank will, in this Code, be referred to as taxa (singular: taxon).
1.2. A taxon (diatom taxa excepted) the name of which is based on a fossil type is a fossil-taxon. A fossil-taxon comprises the remains of one or more parts of the parent organism, or one or more of their life-history stages, in one or more preservational states, as indicated in the original or any subsequent description or diagnosis of the taxon (see also Art. 11.1 and 13.3).
Ex. 1. Alcicornopteris hallei J. Walton (in Ann. Bot. (Oxford), ser. 2, 13: 450. 1949) is a fossil-species for which the original description included rachides, sporangia, and spores of a pteridosperm, preserved in part as compressions and in part as petrifactions.
Ex. 2. Protofagacea allonensis Herend. & al. (in Int. J. Pl. Sci. 156: 94. 1995) is a fossil-species for which the original description included dichasia of staminate flowers, with anthers containing pollen grains, fruits, and cupules, and thus comprises more than one part and more than one life-history stage.
Ex. 3. Stamnostoma A. G. Long (in Trans. Roy. Soc. Edinburgh 64: 212. 1960) is a fossil-genus that was originally described with a single species, S. huttonense A. G. Long, comprising anatomically preserved ovules with completely fused integuments forming an open collar around the lagenostome. Rothwell & Scott (in Rev. Palaeobot. Palynol. 72: 281. 1992) subsequently modified the description of the genus, expanding its circumscription to include also the cupules in which the ovules were borne. The name Stamnostoma can be applied to a genus with either circumscription or to any other that may involve other parts, life-history stages, or preservational states, so long as it includes S. huttonense, but not the type of any earlier legitimate generic name.