From: "Tim Williams" <twilliams_alpha@hotmail.com>
Reply-To: twilliams_alpha@hotmail.com
To: Mickey_Mortimer11@email.msn.com, dinosaur@usc.edu
Subject: Re: Details on Ricardoestesia isosceles
Date: Mon, 26 Feb 2001 12:10:22 -0600
Mickey_Mortimer wrote:
Ricardoestesia Currie, Rigby and Sloan 1990
R. isosceles Sankey 2001
Relationships-
The phylogenetic relationships of Ricardoestesia are obscure due to >the
many plesiomorphies, although it can be safely omitted from >several
groups
(Ornithomimosauria, Segnosauria+Oviraptorosauria, >Alvarezsauridae,
Troodontidae, Eumaniraptora). Perhaps it is related to basal
coelurosaurs,
tyrannosaurs or Bagaraatan.
I've often wondered if _Ricardoestesia_ might actually be a bird. Says
Julia Sankey of one tooth (V-6237) "The tooth is indented at the base as in
bird teeth (Currie, personal commun., 1999)." If _Ricardoestesia_ is
avian,
it may explain why only teeth and a dentary are known for the genus: the
rest of the skeleton was so gracile that it was rarely preserved.
Tim
------------------------------------------------------------
Timothy J. Williams
USDA/ARS Researcher
Agronomy Hall
Iowa State University
Ames IA 50014
Phone: 515 294 9233
Fax: 515 294 3163
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