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 termination -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 may be used unchanged at different ranks.
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 corresponding higher-ranked name.
16.3. When an automatically typified name above the rank of family has been published with an improper Latin termination, not agreeing with 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. 32.7). However, if such names are published with a non-Latin termination they are not validly published.
16.4. Where one of the word elements -clad-, -cocc-, -cyst-, -monad-, -myces-, -nemat-, or -phyton-, being the genitive singular stem of the second part of a name of an included genus, has been omitted before the termination -phyceae, -phycota (algae), -mycetes, -mycota (fungi), -opsida, or -phyta (other groups of plants), 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 indicated at establishment of the group name. These word elements may also be omitted before the termination for subdivision or subphylum as appropriate in each case.
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:
16B.1. In choosing among typified names for a taxon above the rank of family, authors should generally follow the principle of priority.
(c) 2006, by International Association for Plant Taxonomy. This page last updated 12.03.2007 .