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RE: Ceratops (was RE: Pterosaur diversity (was: Re: Waimanu))

Mike Taylor wrote:

Sometimes it's too late.  By the time we had enough new genera that
_Titanosaurus_ was no longer uniquely diagnosable, it was 125 years
old.  By the time we figured out that procoelous caudals are not
synapomorphic for "titanosaurids", Titanosauridae had been established
for the best part of a century.  For that century-and-a-bit,
_Titanosaurus_ and Titanosauridae were good, useful taxa.  That they
are now rightly deprecated doesn't change the fact that they were
historically useful.

I agree - but the word "were" is the crux of this argument. When a taxon is no longer useful, it is probably better to discard it - instead of resorting to heroic efforts to keep it alive.

... but the draft PhyloCode also, of course, also requires that taxa
(i.e. clades) that are named after genera include those genera:

This could be harder to prove. After all, unless an explicit etymology is provided for each clade, it is open to interpretation whether it is named *after* a given genus. For example, we know that when Titanosauria was first named (was it by Bonaparte and Coria, 1993?) it was ultimately named after _Titanosaurus_; but unless this is explicitly stated in the paper, the name could just be a descriptive term in its own right ("titan lizards"). Same for Ceratopsia.

We know that Dinosauria was not named after a genus, because Owen gave reasons for why he came up with this name. But for all intents and purposes, Titanosauria and Dinosauria could be treated the same way because neither were explicitly tied to a specific genus.

Family-level taxa are named after included genera because this practice is mandated by the ICZN. But this is not the case for higher-level taxa (in zoological nomenclature, anyway).

That says to me that it's bad PhyloCode practice, too, to make a name
based on a genus whose affinities can't be rigorously established.

Yes. After all, rigorously establishing the affinities of taxa is the main purpose of PT.