Re: Heterodontosaurids

[<TWILLIAMS@canr1.cag.uconn.edu>]

> 
> Just looking at the old cerapod phylogeny and shaking my head about the
> placement of heterodontosaurids.  If you look at the jugal boss and
> caniniform teeth, don't you see basal pachycephalosaur?  

_Orodromeus_ and _Zephyrosaurus_ also show a jugal boss.  These are 
definitely ornithopods - of the family Hypsilophodontidae (although 
I believe this has been broken up into more than one clade by some 
authors).

> Now if _Lanasaurus_
> is a valid taxon and it does lack the caniniform teeth,

It does?  Maybe it's just a female, or a juvenile, and only males had 
"tusks".

> The only reason I include ceratopsians in a group with
> "heterodontosaurids"/pachycephalosaurs exclusive of _Lanasaurus_ is because
> of the caniniform teeth in _Protoceratops_, which could be because of
> convergence.  

I didn't know _Protoceratops_ had caniniform teeth.

Tim