[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
RE: First New Dino of 2010
Tom Holtz <email@example.com> wrote:
> In the broader systematic implications of this paper, they regard
> Homalocephale as a juvenile of the sympatric Prenocephale, and
> Wannanosaurus and Goyocephale as juveniles of (almost certainly domed)
> otherwise undiscovered adult taxa. Thus there are at present no
> flat-headed adult pachycephalosaurs.
I was a little surprised at this, but I should really have seen it coming, in
light of what was happening to the N. American pacycephalosaur genera.
Interestingly, _Prenocephale_ and _Homalocephale_ were named and described in
the same paper (Maryanska and Osmolska, 1974). _Prenocephale_ was named +
described three pages before _Homalocephale_, so if the two genera are formally
synonymized, then _Prenocephale_ presumably has priority.
Also, the paper states: "_Yaverlandia bitholus_ and _Micropachycephalosaurus
hongtuyensis_ are no
longer believed to represent pachycephalosaurids (Sullivan, 2003; Butler and
Zhao, 2009)." This is certainly true of _Yaverlandia_ (theropod); but the
affinities of _Micropachycephalosaurus_ are a little murkier. Butler and Zhao
(2009) found _Micropachycephalosaurus_ to be a member of the Cerapoda, but the
fragmentary material meant its position could not be resolved further. Thus,
this genus MIGHT be a pachycephalosaur, as Butler and Zhao (2009) note. Dong
(1978) originally reported a thickened skull roof, but this could not be
located. The phylogenetic analysis of Zheng et al. (2009) (in the _Tianyulong_
paper) found _Micropachycephalosaurus_ to be a basal ceratopsian, but I don't
know what the statistical support for this position was.