Giant neosuchian (Crocodyliformes) osteoderm from Upper Cretaceous of Colorado

[Ben Creisler <bcreisler@gmail.com>]

Ben Creisler
bcreisler@gmail.com

A new paper:

John R. Foster & ReBecca K. Hunt-Foster (2015)
First report of a giant neosuchian (Crocodyliformes) in the Williams
Fork Formation (Upper Cretaceous: Campanian) of Colorado.
Cretaceous Research (advance online publication)
doi:10.1016/j.cretres.2015.02.003
http://www.sciencedirect.com/science/article/pii/S0195667115000191




A large osteoderm found in a channel sandstone in the Williams Fork
Formation (“Mesaverde Group”) of northwestern Colorado represents the
first reported evidence of a large neosuchian crocodyliform in the
formation in northwestern Colorado. The osteoderm is of a size and pit
pattern that resembles the large alligatoroid Deinosuchus but the
thickness and shape of the bone suggest possible affinities with the
goniopholidid or pholidosaurid crocodyliform material known from the
Campanian of southern Utah; smaller, similar osteoderms from the
formation may suggest that this form was relatively abundant as
juveniles. Overall faunal similarities of the Williams Fork Formation
are closest to the Kaiparowits Formation of southern Utah also, but
few lower level taxa can be confirmed from the Williams Fork that are
not also known from other areas north and south, suggesting that the
Williams Fork vertebrate fauna comes from the southern end of a
transition zone between possible latitudinal provinces of Laramidia.
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