RE: Allosauroid _Abelisaurus_???

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> T. Mike Keesey
>
> Wow! From the abstract:
> "_Abelisaurus_ shares apomorphic characters with Carnotaurinae, but many
> of these characters are also found in the carcharodontosaurid allosauroid
> _Giganotosaurus_. As it is known only from cranial material lacking
> carnotaurine synapomorphies, _Abelisaurus _may represent a late-surviving
> carcharodontosaurid derivative."
>
> I can't read the paper, but it looks like they are suggesting that
> _Abelisaurus_ is not a ceratosaur at all, but a carcharodontosaurine!
> (Or carcharodontosaurid, depending on your taxonomic preference.) This
> would have some pretty profound implications for ceratosaurian taxonomy.
> (Like the abandonment of _Abelisauria_ and _Abelisauroidea_ -- what would
> we even call these critters? And how many abelisaurs would _Abelisaurus_
> "take with it" into _Carcharodontosaurinae/idae_?)

The authors do not come to the *conclusion* that _Abelisaurus_ is an
allosauroid; in fact, they accept it as an abelisaurid and relative to the
carnotaurines.  However, they do point out (as have others before them) the
anatomical similarities shared by _Abelisaurus_ and _Giganotosaurus_; and
that, because _Abel._ lacks postcranial material, the potential exists that
in the future we COULD find that it is a carcharodontosaur.

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
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