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Re: Sinraptoridae vs. Eustreptospondylidae



At 01:14 AM 12/6/97 PST, Jaemei wrote:
>Just to wonder something, what date was Sinraptoridae coined? The same 
>as when *Sinraptor*?

Yes.

>Anyway, it seems to me that Paul's use of the Eustreptospondylidae-- 
>Metriacanthosaurinae has its valid points, and its inclusion of such 
>"sinraptorids" as *Yangchuanosaurus* and *Metriacanthosaurus* is thereby 
>defunct be date.

A restudy of _Metriacanthosaurus_ could show it to be a "sinraptorid", in
which case Sinraptoridae would be sunk into Metriacanthosauridae.
Eustreptospondylus seems to be more primitive than the sinraptorids, though.

>On a side bar, what horizons were *Afrovenator* and *Deltadromeus* found 
>in?

_Afrovenator_: ?Barremian of Niger.

_Deltadromeus_: Cenomanian of Morocco (& Egypt)

>What is the composition of the specimen of *Afrovenator* and 
>*Monolophosaurus,* or *Bahariasaurus*? This is all unrelated to each 
>other, but who knows?

_Afrovenator_ and _Monolophosaurus_ are known from single, reasonably good
skeletons.  See the appropriate papers (or the appropriate articles in Don
Glut's Dinosaurs: the Encyclopedia) for the precise list.

The appropriate papers are:

Sereno, P.C., J.A. Wilson, H.C.E. Larsson, D.B. Dutheil & H.-D. Sues.  1994.
Early Cretaceous dinosaurs from the Sahara.  Science 266: 267-271.

and

Zhao X.-J. & P.J. Currie.  1993.  A large crested theropod from the Jurassic
of Xinjiang, People's Republic of China.  Canadian Journal of Earth Sciences
30: 2027-2036.

_Bahariasaurus_?  A more difficult case.  Some consider various isolated
elements from the Cenomanian of North Africa as belonging to this genus, but
Sereno et al. consider most everything but the type vertebrate which has
been refered to _Bahariasaurus_ to be _Deltadromeus_.

>Also, just a possibility, does Acrocanthosauridae sound good, with 
>*Acrocanthosaurus* and *Afrovenator* its constituents? This is based on 
>similarities of the pelvis and mandible, as well as the height of Afro's 
>neural spines.
>
It might indeed be possible, but you will have to be more precise as to
WHICH similaritites of the pelvis and mandible (which, incidentally, is
known from only limited material), as well as demonstrating that these
features unite these two taxa outside of other theropods.  (That is,
characters which are also found in _Allosaurus_ would not help to unite the
two).

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