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RE: tyrannosaurid ancestry, raptors and other fun things...
> From: firstname.lastname@example.org [mailto:email@example.com]On Behalf Of
> T. Mike Keesey
> > Mike ,
> > What is the oldest , unambiguous tyrannosauroid found to date ? My
> > references are not clear on this issue . Thanks in advance .
> Seeing as all the non-tyrannosaurid tyrannosauroids are ambiguous, that
> would have to be _Alectrosaurus_, from the Turonian(?).
Well, _Alectrosaurus_ is the oldest NAMED tyrannosaurid.
However, Cenomanian-aged tyrannosaurid teeth are known from the Mussentuchit
Member of the Cedar Mountain Formation, and from Aptian-Albian deposits of
Japan. These show definite tyrannosaurid characters, unlike some of the
semi-tyrannosauriform teeth (e.g., the Gumiarota teeth) which occur earlier.
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): 301-314-7843