But surely "Type, by tautonymy", would be Sula sula, not Sula leucogaster?
Brisson's nomenclature is not standard and somewhat problematic (only his generic names are considered available). Here, the "tautonymy" would result from a species "
Sula" (not binominal) in a genus
Sula. But see below.
This case is discussed by
Sclater 1915.
Thanks; unfortunately I don't understand your last paragraph :-(
Sorry, trying again...
Ornithology has traditionally considered type species are
taxonomic species. Everything that is included by the original author in his genus, and that can be traced to an actual species "that-lives-out-there" is considered eligible as a type species.
The Code considers type species are
nominal species, which are nomenclatural concepts, and have to be traceable down to a unique available name and unique type material.
If you read Sclater's text I linked above: he says Brisson's "
Sula" is the type, then proceeds to identify the taxonomic species that is behind it ("this bird is, to my mind, the Brown Booby"), and finally assigns the first name that he considers available for this species (
Pelecanus leucogaster Boddaert) as the type.
Although this is very much representative of what is usual in ornithology, this is absolutely not what the Code says must be done, on at least two accounts.
1) Many taxonomic species have several available names that apply to them, typically all considered synonyms, only the oldest one being used. You can see these various names as taxonomically equivalent (they refer to the same taxonomic species), but nomenclaturally they are distinct (each one has a distinct type material) and you cannot switch between them freely (they refer to distinct nominal species). Identifying an included taxonomic species does not necessarily allow to identify a unique nominal species. The only way to identify a unique nominal species is to see its available name being cited -- hence this is what the Code asks to do: find available names cited in the OD. If there is none (as is the case for
Morus:
Vieillot only cites "Fou de Bassan Buff.", which is a French vernacular), we should disregard what the original author included in his genus, and proceed to find the first author who included species cited by available names in it: these will be the "originally included species" of the genus.
2) Tautonymy in the current Code exists in two flavors.
- One is "absolute tautonymy" (
Art.68.4): "if a valid species-group name, or its cited synonym, originally included in a nominal genus-group taxon is identical with the name of that taxon, the nominal species denoted by that specific name (if available) is the type species." To have this fulfilled, we'd need to find an available name of the type "
Aus sula Jones" somewhere in the original publication, and this would be the type species. There is no such name here.
Ergo, "
Sula" Brisson is not the type of
Sula by absolute tautonymy as defined in the ICZN.
- The other is "Linnaean tautonymy" (
Art.68.5): "if, in the synonymy of only one of the originally included nominal species in a nominal genus-group taxon established before 1931, there is cited a pre-1758 name of one word identical with the new genus-group name, that nominal species is the type species." To have this fulfilled, we'd need to find a pre-1758 one-word name "Sula" cited as the synonym of one, and only one, of the species included in the genus, and the available name that is attributed by the author to this species would be the type species. Brisson's single-word species name "
Sula" is not pre-1758, is not cited as a synonym, and is not available, hence it definitely doesn't fulfil the conditions.
Ergo, "
Sula" Brisson is not the type of
Sula by Linnaean tautonymy as defined in the ICZN. However, there is a single-word "Sula" cited in the synonymy of
Sula Bassana on
p.504 ("Les habitans de l'Isle Ferroë, S
ULA.
Clus."). Although Brisson's names are not available, his
Sula Bassana is probably interpretable as a recombination of
Pelecanus bassanus Linnaeus, 1758, that is cited in the synonymy as well, and is available. Thus, actually,
Pelecanus bassanus Linnaeus, 1758 could arguably be seen as the type species of
Sula by Linnaean tautonymy, as you originally suggested.
