?Dilophosaurus sinensis

[Josh Smith <smithjb@sas.upenn.edu>]

Mickey Mortimer wrote:

> As an addition to the Yixian dino photos on Mike's web site, I have just
> sent him a photo of the skull of Dilophosaurus? sinensis.  This was
> described in Paleovertebrata Asiatica, which I certainly don't have access
> to and many other list members probably don't either.  Tom and others
> presented evidence at SVP 98 that this isn't really Dilophosaurus, but it
> sure bears a resemblance.  It should be at
> http://dinosaur.umbc.edu/artists/mm.html soon.  I will continue to send Mike
> images from my visits to the RTMP and the Smithsonian in the future, so keep
> an eye out.
>
> Mickey Mortimer

    The specimen is almost certainly NOT _Dilophosaurus_, although there a some
who would certainly argue with that assessment.  Below is the JVP abstract that
Mickey was referring to:


A REASSESSMENT OF THE CHINESE THEROPOD DINOSAUR DILOPHOSAURUS
SINENESIS


*LAMANNA, Matthew C.; SMITH, Joshua B.; YOU Hailu, University of Pennsylvania,
    Department of Earth and Environmental Science, 240 South 33rd Street,
Philadelphia, PA
    19104-6316, lamanna@sas.upenn.edu
HOLTZ, Thomas R., Jr., Department of Geology, University of Maryland at College
Park,       College  Park, MD 20742
DODSON, Peter, University of Pennsylvania School of Veterinary Medicine, 3800
Spruce Street,
    Philadelphia, PA 19104-6045
    Published in the Journal of Vertebrate Paleontology, 18(3):57A.

Numerous peculiarities apparent in the cranial and post cranial anatomy of the
primitive Chinese theropod dinosaur Dilophosaurus sinensis have raised concern
that its taxonomic and systematic placement are in error. Its initial referral
to the genus Dilophosaurus was based largely upon the fact that both the
Chinese animal and the American D. wetherilli possess distinctive paired
nasolacrimal crests that are similar in form. These crests were thought to be
unique to Dilophosaurus, justifying the referral of the Chinese species to that
genus. However, another related taxon (Syntarsus kayentakatae) possesses such
ornamentation as well. Future studies may show that paired crests are
sporadically distributed within Coelophysoidea and thus of limited utility in
the assessment of the interrelationships of this theropod clade.
    Differences concerning premaxillary shape and tooth count, size and
position of the external mandibular fenestra, shape of the infratemporal
fenestra and squamosal, and a derived antorbital tooth row in the American
Dilophosaurus cast considerable doubt upon the referral of the Chinese animal
to the same genus.  Restudy of this species should prove very useful in the
clarification of basal theropod taxonomy, phylogeny, and biogeography.

Yeah, it is VERY preliminary, I know...

--
Josh Smith
Department of Earth and Environmental Science
University of Pennsylvania
471 Hayden Hall
240 South 33rd Street
Philadelphia, PA  19104-6316
(215) 898-5630 (Office)
(215) 898-0964 (FAX)