D. lambei fossils found in Eocene Duchesnean rocks at the Big Red Horizon Site, Presidio County, Texas are dated at ~38.4—38.3 Ma. Other sites include the Badwater Locality 20 Site and Wood Locality Site, Natrona County, Wyoming ~41.8 Ma., Lac Pelletier Lower Fauna Site, Saskatchewan ~42.3 Ma.
Daphoenus, like the rest of its family, was called a "bear dog" because it had characteristics of both bears and dogs. These animals were about the size of the present day coyote. Daphoenus vetus was the largest species. The male skulls could reach up to 20 centimetres (7.9 in) in length. Daphoenus had short legs, and could only make quick sprints; it was not capable of running long distances. It is thought that these animals ambushed their prey, and did some scavenging. Fossil footprints suggested that, like present-day bears, these animals walked in a flat-footed way. Daphoenus dug burrows for their offspring to stay in and hide from their prey.[2]