Lisserpeton bairdi Estes, 1965

Sahni, Ashok, 1972, The vertebrate Fauna of the Judith River formation, Montana, Bulletin of the American Museum of Natural History 147 (6), pp. 319-416 : 349

Lisserpeton bairdi Estes, 1965

The material collected from the Judith River Formation and referable to Lisserpeton consists of a number of atlas and dorsal vertebrae and a fragmentary exoccipital. The Campanian specimens are indistinguishable from those of the Maestrichtian recovered from the Lance Formation, Wyoming, and the Hell Creek Formation, Montana.

DIsCUSSION: The genera Scapherpeton and Lisserpeton are common in the fauna, although the former is more frequent. The Schapherpeton material from the Judith River Formation is identical to that from the large collections obtained from the Lance and Hell Creek formations of Wyoming and Montana. The presence of Lisserpeton in the Judith River Formation extends its geologic range downward and increases its geographic distribution. To date it has been reported from the Lance Formation of Wyoming; from a number of localities near the Fort Peck Reservoir, eastern Montana; and from the late Paleocene of the same region.