[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

re: Rhynchocephalia



If Rhynchosaurs are not related to Sphenodontia, from whence did they
come?

My cladogram tells me already, but I wanted to hear what others are
bettting on.

David Peters
St. Louis

>>>>>


As has been noted previously, I think it's a little unfortunate
that Rhynchocephalia has now become co-opted for this
clade given that, during its history, this name has included
so many disparate groups, all of which (rhynchosaurs,
choristoderes, thalattosaurs, younginiforms, etc) have little
to do with sphenodontians. Indeed Benton (1985) tried to
get rid of the term 'since [it] has become too wide in
application' (p. 147) and wrote that 'The group has clearly
got completely out of hand, and the use of the name
Rhynchocephalia for _Sphenodon_ and its relatives alone
would be confusing' (p. 147). Personally I don't think
Gauthier and certain of his colleagues make the best
decisions when it comes to the naming of newly recognised
clades: he/they have a nasty habit of using old names that,
like Rhynchocephalia, come burdened with a history. Sauria
and Pseudosuchia are other examples of this sort of thing.
On the other hand, the _Gephyrosaurus_ + Sphenodontia
clade needed a name, and sphenodontians are the only
group that have always formed the 'core' of
Rhynchocephalia.

Refs - -

Benton, M. J. 1985. Classification and phylogeny of the
diapsid reptiles. _Zoological Journal of the Linnean
Society_ 84, 97-164.

Gauthier, J., Estes, R. & de Queiroz, K. 1988. A
phylogenetic analysis of Lepidosauromorpha. In Estes, R. &
Pregill, G. (eds) _Phylogenetic Relationships of the Lizard
Families_. Stanford University Press, pp. 15-98.

- --
Darren Naish
School of Earth & Environmental Sciences
University of Portsmouth UK, PO1 3QL