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Re: SVP Preview

In a message dated 9/27/02 5:20:25 PM EST, qilongia@yahoo.com 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.