Re: Segnosaurs Analyzed as Prosauropods

["Mickey Mortimer" <Mickey_Mortimer11@msn.com>]

ekaterina amalitzkaya wrote-

> Also has Mr. Mortimer examined the state of the coronoid in the
> Ornithomimosaurs: Is it not reported to be missing in Orinithoms and
> Therizis but present though in a peculiar form in the oviraptorosaurs.

Here's the convenient list I wrote earlier-
Theropods with a coronoid-
Dilophosaurus, Carnotaurus, Monolophosaurus, Sinraptor, Allosaurus,
Tyrannosauridae, Caudipteryx?, Oviraptoridae, Dromaeosaurus, Velociraptor,
Bambiraptor
 Theropods supposedly lacking a coronoid-
Ornithomimidae, Therizinosauridae, Chirostenotes, Shuvuuia, Troodontidae,
Archaeopteryx, Gobipteryx, Ornithurae

Ornithomimids are reported to lack a coronoid, though descriptions or
figures of their mandibles in medial view are extremely rare.  They are
generally coded as absent for that group and one is missing from the figure
of Garudimimus' mandible in Barsbold 1983.  However, Osmolska et al. (1972)
report the presence of a coronoid in Gallimimus and illustrate it.  Holtz
(pers. comm. 2000) says that it was missidentified.  Neither Erlikosaurus
nor Segnosaurus has a coronoid preserved in otherwise complete mandibles
(Barsbold and Perle, 1980; Clark et al., 1994).  The absence of coronoids in
these theropods must be viewed with caution however, as oviraptorids were
also described and illustrated (eg. Barsbold, 1983) as lacking coronoids,
but a delicate coronoid was found in an oviraptorid skull recently (Clark et
al., 2000).  There is a small bone in a Caudipteryx specimen (BPM 0001) that
I think looks like a coronoid, but the bone is absent from well preserved
mandibles of Chirostenotes (Currie, et al., 1993).

Mickey Mortimer