Three Late Cretaceous albanerpetontids are identified, diagnosed, and described herein based on jaws and frontals from the North American Western Interior: Albanerpeton nexuosus Estes, 1981 and A. galaktion Fox & Naylor, 1982 (both Campanian and Maastrichtian) and A. gracilis n. sp. (middle Campanian). Membership of each in Albanerpeton Estes & Hoffstetter, 1976 is founded on diagnostic character states of the frontals and on premaxillary synapomorphiesthat diagnose less inclusive clades in the genus. A. nexuosus is a member of the robust-snouted clade, whereas A. galaktion and A. gracilis n. sp. belong in the gracile-snouted clade. Species of Albanerpeton appear to have evolved largely in isolation through the Late Cretaceous in the Western Interior. Although the three species were broadly sympatric, differences in cranial structure and inferred body size imply that each favored a different ecological niche.
Albanerpeton, Albanerpetontidae, Campanien, Crétacé, Maastrichtien, Amérique du Nord