Re: Podokesauridae, Problems of Nomenclature Returned

["Jaime A. Headden" <qilongia@yahoo.com>]

  Well, the big email I was writing when my computer blue-screened me was
lost, so here's another attempt to render my reply...

George Olshevsky (Dinogeorge@aol.com) wrote:

<I wouldn't be so sure that Podokesaurus is a synonym of Coelophysis. 
Look at the differences that purportedly separate Coelophysis from
Eucoelophysis.  They're at least as great as the differences that separate
Podokesaurus from Coelophysis.  Also Podokesaurus is considered Early
Jurassic, somewhat later than Coelophysis and Eucoelophysis (still Late
Triassic).  The type specimen of Podokesaurus holyokensis was lost in a
fire, but casts do survive.  It's supposed to be a juvenile.>

  I like the idea of the podokesaur/coelophyse implosion. However, as for
*Podokesaurus* itself, I was to understand that it was indeterminate
whether the material could be differentiated ontogenetically. The late Ned
Colbert and Dale Russell had doubts as to the specimen's age, as well as
the nearly complete lack of apomorphies. The material was damaged and
poorly preserved, even before the fire, no apomorphies that were not
size-related could be found. These are also brought up. All features of
the casts (the YPM cast is the best) indicate that apomorphies that are
present only seem to ally it with *Coelophysis*, and they cannot be
distinguished on morphology. Of course, most of the podokesaurid features
in the group that show considerable variation are the skull anyway, which
is lacking in *Podokesaurus*. It is prudent therefore to assign
*Podokesaurus* as either an indeterminate species of *Coelophysis*, to *C.
bauri*, or as Podokesauridae indet.. Nonetheless, nothing indicates that
*Podokesaurus* is _not_ closer to *Coelophysis* than any other group of
theropod, and this still means bad news for "Coelophysidae."

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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