AVIMIMUS

[Tetanurae@aol.com]

Greg Paul wrote:
<<This is off the cuff, but Avimimus has a much more avian skull than
Caudipteryx. Slender jugal-quadratojugal bar, lack of postorbital. Fused hand
too. Other features. Probably not closely related.>>

As I have said on this list before, the skull of Avimimus is not really that
bird-like, but much more similar to those of oviraptors.  The slender jugal
bar is also seen in oviraptors, but in basal birds.

The postorbital-jugal bar is busted off in both the postorbital and jugal, so
it can't be known if it is broken or not.  In my opinion, since there is no
evidence of Avimimus actually being a bird with a kinetic skull, one should
reconstruct it with the PO-J bar intact.

Other parts of the anatomy, such as the premaxilary with crenulations, and the
antiorly displaced AOF with accesory foramina preserved in the rostrum
fragment show that it probably belongs to an oviraptorosaur, and not any kind
of avian.

The carpus probably does not belong to the head, as the head is from an
oviraptorosaur and the hand is from an ornithothoracian bird.  The feet
probably belong to a mononykine bird.

As for the rest of the skeleton, who knows, could belong to an oviraptorosaur,
could be from something like Bagaraatan, could be something completely new and
different.

Peter Buchholz
Tetanurae@aol.com