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Re: RAUHUT ON BASAL THEROPODS



Nick Gardner wrote-

> >_Neovenator_ is
> >sister to Carcharodontosauridae and sinraptorids are the
> >sister-taxon to _Neovenator_ + carcharodontosaurids as
> >these taxa share an expanded ischial 'boot', postorbital
> >projection into orbit and dorsal projection on the parietals
>
> Isn't the expanded ischial boot a plesiomorphy found in spinosauroids and
> ceratosaurs?

In his thesis, this character is defined as having a boot more than twice
shaft width.  Rauhut (1999) does code this as present in ceratosaurs, but
not in megalosauroids/spinosauroids.

> What sinraptorid has a postorbital projection into the orbit?

Sinraptor dongi and S. hepingensis, but I don't see it in Yangchuanosaurus.

> Dorsal projection on the parietals, is that the supraoccipital crest?

Yes, also called a nuchal crest.

> Also, here- http://www.cmnh.org/dinoarch/1996Feb/msg00816.html
>
> Has anyone confirmed this?  Is it possible? *Compsognathus* with
> arctometatarsalian feet?

Not present.  Photos in Ostrom (1978) confirm the third metatarsal is
slightly expanded proximally if anything.

David Marjanovic wrote-

(referring to the ischial boot)
> Could it be size-related, a weight-bearing feature?

Ornithomimids have it, tyrannosaurids don't.  Not the distribution one
expects of a size-related character.

Tim Williams wrote-

> In the event _Spinosaurus aegyptiacus_ is a chimera, what specimen gets to
> carry the name?  Is the dentary or one or more of the tall-spined
vertebrae
> the holotype/lectotype for the species?

One could only hope the dorsal vertebrae.  Don't want another
Altispinax-like situation.

Mickey Mortimer