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Heterodontosaurids



iHola!

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?  Now if _Lanasaurus_
is a valid taxon and it does lack the caniniform teeth, wouldn't this be a
good candidate for sister-group to Marginocephalia, perhaps something like:

(_Lanasaurus_ (Ceratopsia (Heterodontosauridae + Pachycephalosauria)))

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 understand that the idea of heterodontosaurids as basal members of
Ornithopoda is beginning to lose favor, but have not seen a recent published
phylogeny where it was not considered so.  Things like _Hypsilophodon_ seem
more primitive in the brevity of the posteroventral projection of the
premaxilla, retention of more than 3 premaxillary teeth, more primitive
"cheek" teeth, and morphology of the quadratojugal, yet have been considered
more advanced ornithopods than _Heterodontosaurus_.  Doesn't removal of the
latter from Ornithopoda seem most likely to be right?  

Just things to ponder (non-theropod too).

Jack