Re: Re: Re: Not carnosaurs, this time...

[Thomas_R_HOLTZ@umail.umd.edu (th81)]

Jonathan Wagner wrote:

>        Well, as much as any cladogram can, it certainly does not refute
>such a reference (although it does refute the placement of A. sternbergi in
>Albertasaurus *or* Gorgosaurus (no, TRHJr, size of teeth was not a
>character), but I am somewhat skeptical of this, since it is largely based
>on sexual selectors (lacrimal horns), and the FMNH has a lot on common with
>Dapletosuarus and arctunguis/sarcophagus.

There is an interesting aspect of the ischia of sternbergi and novojilovi
that few have noticed before, but I don't know if it's significant...

>P.S.  For all you taxonomists out there, why do we call these the
>Tyrannosauridae, a simple family, when the more similar Ornithomimids get a
>supra-familial taxon?

Because Barsbold never got around to naming "Tyrannosauria" (although Mike
Brett-Surman and George Olshvesky did).

>I think Tyrannosauridae should be limited to a node-based taxon of the
>most primitive taxon now referred to Albertosaurus + T. rex, and the
>outgroups should be placed in Tyrannosauroidea (all thereopods closer to
>T. rex than to Ornithomimus).

This has been suggested by many authors, most recently Carpenter (in 1992).

>        Which then brings up, what do we call the noe of Ornithomimus +
>Tyrannosaurus.  Tom Holtz?

No, "Tom Holtz" is not a suitable name for that node, since my dad has
priority over it... :-)

I'd just as soon leave that node unnamed, and use the stem-based
"Arctometatarsalia" for it.

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:th81@umail.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661

"There are some who call me...  Tim."