Re: Avaceratops and Ceratops (was Re: THE NEW ISH OF JVP)

["Mickey Mortimer" <mickey_mortimer@email.msn.com>]

First of all, does anyone know where Penkalski and Dodson place
Turanoceratops in their new paper?  Above or below Avaceratops?

Tim Williams wrote-
>On a completely separate topic, a while back somebody mentioned that the
new
>ornithomimosaur from Thailand does NOT have an arctometatarsal pes.  It
>does.  Buffetaut and Suteethorn's preliminary descriptions and figures
spell
>that out.


This is only because they use the term "arctometatarsal" incorrectly.  Note
that their description reads "proximally, however, the third metatarsal of
the Thai form is still visible in anterior view, as a thin sliver of bone
between the proximal ends of metatarsals II and IV".  And indeed, the figure
illustrates this well- you can still see metatarsal III just fine between II
and IV in both proximal and anterior views.  Correct me if I'm wrong, but
isn't the arctometatarsalian condition that in which metatarsals II and IV
contact each other proximally?  The Thai form is pretty close to
arctometatarsaly (as would be expected in an ancestor of truly
arctometatarsalian forms), but isn't quite there yet.  Add this to
Harpymimus and you've got fairly good evidence of the ornithomimids
developing arctometatarsaly independently of other coelurosaurs.

Mickey Mortimer