International Code of Botanical Nomenclature

(Tokyo Code), Electronic version


CHAPTER II. NAMES OF TAXA (GENERAL PROVISIONS)

SECTION 2. TYPIFICATION

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 purposes 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 defined 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 simultaneously 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. 22.5, 22.6, and 37.2) or designated by the author of the name. If no type of a previously or simultaneously published species name was definitely included, a type must be otherwise chosen, but the choice is to be superseded if it can be demonstrated that the selected type is not conspecific with any of the material associated with the protologue.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 Anacyclus 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.

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 conspecific with Linden's collection Swart's type designation cannot be superseded, even though the Spruce specimen became the type of Paullinia paullinioides Radlk. (1896), because 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 indirect) 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 included species.

Ex. 4. Physconia Poelt has been conserved with the specimen "'Lichen pulverulentus', Germania, Lipsia in Tilia, 1767, Schreber (M)" as the type.

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.

10.5. The author who first designates a type of a name of a genus or subdivision 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 another 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. 5. 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 therefore be superseded.

*Ex. 6. 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 Britton & 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 generic name is the same as that of the corresponding alternative name (Art. 18.5 and 19.8).

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. 22.5 and 22.6.

Recommendation 10A

10A.1. When a combination in a rank of subdivision of a genus has been published 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.


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