X-Nico

Caseosaurus

Caseosaurus was described and named by A. P. Hunt, Spencer G. Lucas, Andrew B. Heckert, Robert Sullivan and Martin Lockley in 1998 and the type species is Caseosaurus crosbyensis.

Ferganocephale

Robert Sullivan however, in 2006 disputed the pachycephalosaur classification, finding "few of the features ... are characteristic of pachycephalosaur teeth," citing the lack of serrations on the teeth, and concludes the specimens are "too incomplete for identification".

Ornithomimus

Beginning in 1997, Robert Sullivan regarded O. velox and O. edmontonicus as junior synonyms of O. antiquus.

Saurornitholestes

In 2006 Robert Sullivan named and described a second species, Saurornitholestes robustus, based on holotype SMP VP-1955, a left frontal.

Stenopelix

But paleontologists Richard Butler and Robert Sullivan nonetheless view the species as being Marginocephalia incertae sedis, rejecting the presumed synapomorphies with the Pachycephalosauria as incorrect identifications or lacking cogency because of a possible presence in ceratopsian groups.

see also