[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
RE: Stenopelix valdensis
Michael Lange wrote-
I heard that Sullivan has recently made Stenopelix an Ornithischia indet.
I've seen the specimen >myself some years ago on display at the small
Geological Museum in Goettingen. The skull is not >present, but should have
been preserved when the quarry workers found the skeleton (when I >recall
correctly). Still, its a nice and interesting specimen. What are the
reasons why Sullivan says >its no Marginocephalian anymore.
Because few pachycephalosaurs preserve good postcrania, so he's far too
cautious about referring postcrania to the clade (if he can't prove that
most pachycephalosaurs had a trait, he considers the trait 'weak').
Also he questioned the absence of pachycephalosaur postcranial
synapomorphies in outgroups, with no examples to show why he questions it.
Finally, he likes Coombs (1979) outdated idea of pachycephalosaurs being an
ankylosaur sister group better, and Stenopelix lacks a pelvic character
those two clades share. Needless to say, Yinlong nicely blows that proposed
relationship out of the water.
So basically Sullivan's reasons are worthless and should not be given any