Tiffanian

Barylambda (Greek: "heavy" (baros), "lambda" (lambda) in a reference to larger size than that of Pantolambda) is an extinct genus of pantodont mammal from the middle to late Paleocene, well known from several finds in the Wasatchian (NALMA classification) DeBeque Formation of Colorado and the Clarkforkian Wasatch Formation to Tiffanian Fort Union Formation in Wyoming. Three species of Barylambda are currently recognized. The creature likely lived a life similar to that of a modern tapir, browsing on foliage and soft vegetation. Barylambda seems to have been quite successful for an early pantod

Periptychus is an extinct genus of mammal belonging to the family Periptychidae. It lived from the Early to Late Paleocene and its fossil remains have been found in North America.

Ignacius is a genus of extinct mammal from the early Cenozoic era. This genus is present in the fossil record from around 62-33 Ma (late Torrejonian-Chadronian North American Land Mammals Ages). The earliest known specimens of Ignacius come from the Torrejonian of the Fort Union Formation, Wyoming and the most recent known specimens from Ellesmere Island in northern Canada. Ignacius is one of ten genera within the family Paromomyidae, the longest living family of any plesiadapiforms, persisting for around 30 Ma during the Paleocene and Eocene epochs. The analyses of postcranial fossils by pale