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Ornithopoda + (Heterodontosauridae + Marginocephalia) phylogeny
I've finally gotten a copy (although not pdf) of the Hongshanosaurus paper,
and it does include an explicit numerical phylogenetic analysis of
ornithischians that supports the phylogeny in the subject line.
There are only 7 taxa used, and 44 characters (all cranial), so this could
and should be expanded in the future. However, here are the results, using
the taxonomy in that paper:
Neornithopoda (!?!?) (reference is too Cooper 1985, but I can't recall
taxa were included in this...)
Ideally an advanced version of this analysis would be included many more
taxa (heck, we need one anyway to test most aspects of non-stegosaur,
non-ankylosaur, non-iguanodontian, non-ceratopsian ornithischian
interrelationships!!), but it is a good starting point.
Characters supporting Neornithopoda are:
*Preorbital length: 50-40%(1); less than 40%(2), basal skull length
*Jugal lateral expansion: present(1)
*Jugal lateral expansion position: from the caudal end of the jugal(1)
*Predentary tooth number: less than 5(1)
Can't say I much like a Neornithopoda that doesn't necessarily include
Camptosaurus, Iguanodon, and the hadrosaurids (i.e., the critters for whom
the clade was originally coined), but it isn't explicitly defined here.
Thomas R. Holtz, Jr.
Department of Geology Director, Earth, Life & Time Program
University of Maryland College Park Scholars
College Park, MD 20742
Phone: 301-405-4084 Email: email@example.com
Fax (Geol): 301-314-9661 Fax (CPS-ELT): 301-405-0796