Re: Shuvosaurus

["Tim Williams" <twilliams_alpha@hotmail.com>]

Rob Gay wrote:

> > However, the skull of _Gojirasaurus_ is unknown, so maybe any teeth
> > associated with the postcranial remains belong to another animal -  like a
> > scavenger that happened by the carcass.<
> Are the associated teeth coelophysoid though?

Apparently not (although I believe Carpenter [1997] described the tooth as
coelophysoid).

Says Oliver Rauhut: "The tooth referred to _Gojirasaurus_, on the other
hand, cannot be referred to this taxon with any certainty, since very
similar teeth are present in crurotarsan archosaurs, such as poposaurids
(GALTON 1985a).  In this respect, the presence of a premaxilla of the
edentulous theropod _Shuvosaurus_ in the same quarry is interesting. The
holotype skull of _Shuvosaurus_ is c.17 cm long (CHATTERJEE 1993a), but
represents a juvenile individual, indicating that adult _Shuvosaurus_ would
have been among the largest known Triassic theropods. Since the holotype of
_Gojirasaurus_ represents the largest theropod postcrania known from the
Triassic of North America (CARPENTER 1997), and a premaxilla of a large
individual of _Shuvosaurus_ was found in the same quarry (PARRISH &
CARPENTER 1986: Fig. 11.8, CARPENTER 1997), it seems quite possible that
_Gojirasaurus quayi_ CARPENTER, 1997, might be a junior synonym of
_Shuvosaurus inexpectatus_ CHATTERJEE, 1993a. However, given the uncertain
association of the remains, and the lack of comparable elements in the
holotype specimens, both taxa are treated separately here."

> What about the other elements
> assigned to _Gojirasaurus_? Do they match up to the same elements in
> _Shuvosaurus_?

According to Oliver, the referral of the postcranial material to
_Shuvosaurus_ is also highly uncertain...

"However, only the cranial parts that show some overlap with the holotype
are accepted here as belonging to this taxon [_Shuvosaurus inexpectatus_],
since all the material came from the Post Quarry in the Dockum Group of
Texas, which has yielded hundreds of specimens of all kinds of Triassic
vertebrates (CHATTERJEE 1983, 1984, 1985, 1991, 1993a, LONG & MURRY 1995),
and thus the association of postcranial material such as an isolated scapula
and tibia, are rather questionable."

Sound familiar?



Tim

------------------------------------------------------------

Timothy J. Williams

USDA/ARS Researcher
Agronomy Hall
Iowa State University
Ames IA 50014

Phone: 515 294 9233
Fax:   515 294 3163




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