DIVISION II. RULES AND RECOMMENDATIONS
CHAPTER II. STATUS, TYPIFICATION, AND PRIORITY OF NAMES
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. 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. 22.6, 22.7,
37.1 and 37.3)
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must be otherwise chosen, but the choice is to be superseded if it can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 Anonynous, 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. 10),
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 collected by Spruce 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
Linden
1360. As long as the Spruce specimen is considered to be
conspecific with Linden's material, 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superseded, even though the Spruce specimen became the type of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 last 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 (1965) was originally conserved with the specimen
"'Lichen pulverulentus', Germania, Lipsia in
Tilia, 1767,
Schreber (M)" as the type. That specimen is the type of
P. pulverulacea Moberg (1979), which name is now cited in the type entry in
App. III.
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.
Ex. 5. Pseudolarix Gordon
(1858) was conserved with a specimen from the Gordon herbarium as its
conserved type. As this specimen is not the type of any species name,
its accepted identity "[=
P. amabilis (J. Nelson) Rehder ... ]" has been added to the corresponding entry in
App. III.
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. 6.
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 under Art. 10.5(b). For example, Fink had designated
Biatorina griffithii (Ach.) A. Massal. as the type of
Biatorina
A. Massal.; but his choice was superseded when the next subsequent
designation, by Santesson (in Symb. Bot. Upsal. 12(1): 428. 1952),
stated a different type,
B. atropurpurea (Schaer.) A. Massal.
*Ex. 7. 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 Anonymous, 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 19.7).
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.
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.
(c) 2006, by International Association for Plant Taxonomy. This page last updated
12.03.2007
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