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RE: OLD ORNITHOMIMOSAURS
> From: firstname.lastname@example.org [mailto:email@example.com]On Behalf Of
> David Marjanovic
> > Well, we honestly don't have any confirmed tyrannosauroids from
> the Middle
> > Jurassic (that is, nothing which has been demonstrated as closer to
> > tyrannosaurids than to all other named clades of theropod), and the
> > troodontid teeth are just teeth.
> I was speaking, er writing, of the infamous Iliosuchus...
Which is what I figured. However, as I said: we don't have any confirmed
tyrannosauroids from the Middle Jurassic.
An aside: there are a LOT of good websites out there, many by people on this
list, which show just about every non-avian dinosaur genus placed on the
tree. This must be taken with amazingly large chunks of salt!! The vast
majority of genera have never been subjected to phylogenetic analysis: their
addition to a data run *might* result in their placement on the tree at the
indicated spot, or it could be elsewhere, or indeed the addition may cause a
realignment of other taxa previously included in previous studies.
So, as a general warning: unless you can find the original source study,
treat any big cladogram on the web (or elsewhere) as even more provisional
than a standard analysis.
> > Well, I agree that it isn't a Triassic ornithomimosaur, but
> Oliver Rauhut
> > has offered another alternative: that _Shuvosaurus_ is a
> specialized basal
> > theropod.
> Interesting... Where would it lie on a cladogram?
Well, an exceedingly interesting question, as Rauhut DID run it in his
(as-yet unpublished) analyses, which transformed the traditional members of
Ceratosauria into a paraphyletic series relative to Tetanurae (and even made
Coelophysoidea a paraphyletic series relative to the
abelisaur-_Elaphrosaurus_-_Ceratosaurus_-Tetanurae clade). If memory
serves, _Shuvosaurus_ fell among or just "inside" the coelophysoid-grade
Thomas R. Holtz, Jr.
Department of Geology Director, Earth, Life & Time Program
University of Maryland College Park Scholars
College Park, MD 20742
Phone: 301-405-4084 Email: firstname.lastname@example.org
Fax (Geol): 301-314-9661 Fax (CPS-ELT): 301-405-0796