Previously reported and new specimens of marine turtles from the late Campanian of
Alberta, Canada, provide additional information on the diversity and distribution
of chelonioid turtles at this time. An articulated carapace from the Bearpaw Formation
previously interpreted as Lophochelys niobrarae is considered to be a juvenile of
a specifically indeterminate chelonioid and is referred to Lophochelys sp. Isolated
neurals and a hyoplastron from nonmarine estuarine deposits in the uppermost beds
of the Dinosaur Park Formation are tentatively referred to Lophochelys sp. These specimens
suggest that this chelonioid could enter freshwater environments. A new chelonioid,
Kimurachelys slobodae gen. et sp. nov., is recognized on the basis of two mandibles
and a maxilla from the uppermost beds of the Dinosaur Park Formation of southeastern
Alberta. A partial postcranial skeleton of an indeterminate chelonioid from the Bearpaw
Formation provides additional evidence that chelonioids of this formation included
taxa that were phylogenetically intermediate between chelonioids of the late Santonian
and members of the crown group.
