CHAPTER IV. EFFECTIVE AND VALID PUBLICATION

SECTION 2. CONDITIONS AND DATES OF VALID PUBLICATION OF NAMES

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 effectively 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 diagnosis 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.”, both validly published under Art. 42 by a single Latin diagnosis.

Ex. 2. Presl did not validly publish “Cuscuteae” (in Presl & Presl, Delic. Prag.: 87. 1822) as the name of a family (see “Praemonenda”, pp. [3-4]) by direct reference to the previously and effectively published description of “Cuscuteae” (Berchtold & Presl, Přir. Rostlin: 247. 1820) because the latter is the name of an order (see Art. 18 *Ex. 4).

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 previously and effectively published description or diagnosis of a genus or subdivision of a genus.

Ex. 3. Validly published generic names: Carphalea Juss., accompanied by a generic description; 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. Veron. Suppl.: 73. 1754), accepted there but without a generic description or diagnosis, validly published by indirect reference (through the title of the book and a general statement in the preface) to the generic diagnosis and further direct references in Séguier (Pl. Veron. 1: 117. 1745).

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 effectively published description or diagnosis of a species or infraspecific taxon. A name of a species may also be validly published (c), under certain circumstances, 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 indicates that more than one species belongs to the genus in question.

Ex. 4. Trilepisium Thouars (1806) was validated by a generic description but without mention of a name of a species. T. madagascariense DC. (1825) was subsequently proposed 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.