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Re: SVP Preview
In a message dated 9/27/02 5:20:25 PM EST, firstname.lastname@example.org writes:
<< What the ICZN does not govern is the endings of nomina, such as -oidea;
just ending a taxon name thusly does not make it a superfamily, and if I
could remember the name, I could tell you of one small fossil reptile or
mammal "genus" name that ends in -oidea, but I see no one turning it into
a superfamily as a consequence. This suggests that endings have no ranking
significance, and the fact that some taxa have ranks is because they are
explicitly provided. Sereno did not rank Torvosauroidea, nor does he and
his colleagues any other name they have proposed, and nor have Holtz, etc. >>
But Sereno et al. did change the name to Spinosauroidea regardless.
Here is Article 29.2 of the 2000 ICZN verbatim:
29.2. Suffixes for family-group names. The suffix -oidea is used for a
superfamily name, -idae for a family name, -inae for a subfamily name, -ini
for the name of a tribe, and -ina for the name of a subtribe. These suffixes
must not be used at other family-group ranks. The suffixes of names for taxa
at other ranks in the family-group are not regulated.
29.2.1 Names in the genus and species groups which have endings identical
with those of the suffixes of family-group names are not affected by this
Granted that having the ending -oidea doesn't force a group name to be at the
superfamily level, but when a group name (1) ends in -oidea and (2) includes
with no intermediate levels names that had previously been ranked at the
family-level and that have the family-level ending -idae, then it carries an
implicit superfamily rank and is subject to ICZN rules.
I remember that this problem surfaced with Pterodacyloidea and
Rhamphorhynchoidea, which were ranked as suborders. I changed them in MM #2
to Pterodactyloidia and Rhamphorhynchoidia so that they would not be
misconstrued as superfamilies; otherwise one could have the suborder
Pterodactyloidea containing as a proper subset the superfamily
Pterodactyloidea (for example).
Rankless hierarchies are fine, but if you have no conventions concerning the
formation of names, you quickly lose track of where things are in the
hierarchy. Quick, without looking it up, tell me how these taxa might be
nested: Dinosauromorpha, Dinosauriformes, Dinosauria, Eudinosauria,
Dinosauroidea. Or Sauropoda, Eusauropoda, Macronaria, Titanosauriformes,
Titanosauromorpha, Somphospondyli, Titanosauria, Diplodociformes,
Diplodocimorpha. But given, e.g., Tyrannosauria, Tyrannosauroidea,
Tyrannosauridae, Tyrannosaurinae, Tyrannosaurini, and Tyrannosaurina, once
you know the endings convention, you can immediately see that those names are
in a nested sequence, rank or no rank.
Names of taxa are supposed to be a mnemonic aid to retrieving information
about low-level taxa such as species and genera. This function is lost when
it takes more effort to remember what level in a hierarchy a name falls than
it does to remember the low-level taxa individually.