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RE: Ceratops (was RE: Glishades ericksoni, ...)
Thomas R. Holtz, Jr. <email@example.com> wrote:
> It depends on what the agreed upon definition of Ceratopsidae is
> to be. If it is (for example) Centrosaurus + Chasmosaurus, than
> Ceratops might well be a non-ceratopsid. If instead Ceratopsidae is
> defined as Ceratops + Centrosaurus + Chasmosaurus, than it would be
> included by definition, but might be outside Chasmosaurus >
> Centrosaurus and Centrosaurus > Chasmosaurus.
But... we'll never know where _Ceratops_ sits in ceratopsian phylogeny.
_Ceratops_ is *never* included in a phylogenetic analysis, because it is a
I'm not saying _Ceratops_ *should* be included in a phylogenetic analysis; I'm
only saying it *can't* be. This simple fact makes it impossible to determine
the content of Ceratopsidae if _Ceratops_ is a specifier. For example, what if
_Avaceratops_ comes out as a sister taxon to the Chasmosaurinae+Centrosaurinae
clade. Is _Avaceratops_ a ceratopsid? We could only know this if _Ceratops_
is also included the analysis. But it isn't...
T. Michael Keesey <firstname.lastname@example.org> wrote:
> Probably the best solution, since both relevant
> nomenclatural codes (ICZN and the draft PhyloCode) require Ceratops
> montanus to be within Ceratopsidae by definition.
IMHO, the best solution is to abandon Ceratopsidae altogether. We've abandoned
other family-level names that have been deemed to be based on dubious genera
(Deinodontidae, Trachodontidae, Titanosauridae, etc), so why not abandon
Ceratopsidae too? Having a definition of Ceratopsidae that includes
_Ceratops_, for the sole purpose of maintaining the name Ceratopsidae, strikes
me as special pleading.