New Cranial Material of Gilmoremys lancensis (Testudines, Trionychidae) from the Hell Creek Formation of Southeastern Montana, U.S.A.

@article{Joyce2016NewCM,
  title={New Cranial Material of Gilmoremys lancensis (Testudines, Trionychidae) from the Hell Creek Formation of Southeastern Montana, U.S.A.},
  author={Walter G. Joyce and Tyler R. Lyson and Scott A. Williams},
  journal={Journal of Vertebrate Paleontology},
  year={2016},
  volume={36}
}
ABSTRACT Plastomenidae is a speciose clade of soft-shelled turtles (Trionychidae) known from Campanian to Eocene deposits throughout western North America. We here describe two large skulls from the Upper Cretaceous (Maastrichtian) Hell Creek Formation of Carter County, Montana, that document the adult morphology of the plastomenid Gilmoremys lancensis. Whereas juveniles of this species, as previously documented by five subadult skulls, have narrow skulls, a narrow processus trochlearis… 
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