Wednesday, November 30, 2011

Thescelosaurus assiniboiensis

A new basal ornithopod dinosaur (Frenchman Formation, Saskatchewan, Canada), and implications for late Maastrichtian ornithischian diversity in North America. 2011. Brown, C.M., et al. Zoological Journal of the Linnean Society. 163: 1157-1198

Abstract [edit]: A small, articulated basal ornithopod skeleton from the Frenchman Formation (late Maastrichtian) of Saskatchewan, previously referred to the taxon Thescelosaurus, differs from both recognized species of this taxon (Thescelosaurus neglectus and Thescelosaurus garbanii). We recognize this specimen as the holotype of a new species, Thescelosaurus assiniboiensis sp. nov.

Identification of a third species of Thescelosaurus from the late Maastrichtian of North America suggests that this taxon was more diverse than previously recognized, and shows an increase in diversity from the Campanian through the late Maastrichtian, contrasting the trends seen in most other ornithischian clades.