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Re: two new papers

At 10:27 PM 10/5/98 -0700, Jamie wrote:

>May vindicate my little idea about *Garudamimus* having a reversed
>arctomet structure, for both the outgroup to Ornithomimosauria
>(Troodontidae) and the outgroup to that group (Bullatosauria, but you
>knew that, didn't you? ;) being Tyrannosauroidea) one would say it is
>more parsimonious to indicate a reversal than the ornithomimids
>attaining an arctomet with extactly the same condition and structre as
>their larger and smaller relatives. Right?

Well, actually, there is not too much "reversed" about _Garudi_'s foot
anyway.  It actually is pinched: see the illustration of it in the Currie &
Russell 1988 paper on _Chirostenotes_, where it is improperly labeled as

_Harypmimus_, though, might be reversed.

Both guys have relatively short metatarsi for ornithomimosaurs, but actually
so does the type of _Ornithomimus velox_ (something I've been wondering
about for awhile).

At 04:38 PM 10/5/98 -0700, Stan Friesen wrote:

>>Taquet, P. & D.A. Russell.  1998.  New data on spinosaurid 
>>dinosaurs from the Early Cretaceous of the Sahara.  C.R. Acad. 
>>Sci. Paris, Sciences de la terre et des planetes 327: 347-353.
>>New specimens of spinosaurids from North Africa: a snout 
>>referred to _Spinosaurus maroccanus_, ...
>Yikes! I don't have this species.  When, and by whom, was it described?

Russell, D.A.  1996.  Isolated dinosaur bones from the Middle Cretaceous of
Tafilalt, Morocco.  Bull. Museum national d'Histoire naturelle, Paris, serie
4  18: 349-402.

>>        Eumaniraptora
>>          Deinonychosauria
>>            Troodontidae
>>            Dromaeosauridae
>>          Avialae
>Dromaeosaurids and Troodontids back together!?!?
>How solid is this?

Well, there are some pretty good characters to unite troodontids and
dromaeosaurids.  However, there are also some entirely different pretty good
characters to unite troodontids and ornithomimosaurs.  On top of that, there
are a few pretty good characters to unite troodontids and the
oviraptorosaur-therizinosauroid clade, and a handful of good characters to
unite troodontids and tyrannosaurids.  As you might imagine, troodontids
will be featured in my talk at the Ostrom Symposium, "Arctometatarsalia
Revisited: The problem of homoplasy in reconstructing theropod phylogeny".
(The short version: this isn't due to the incomplete nature of the
specimens: the characters are really there.)

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