Borophagus diversidens. Illustration and photo-reconstruction of the ancient dog Borophagus with a scavenged carcass. Borophagus diversidens (devouring glutton) is an extinct species of the genus Borophagus of the subfamily Borophaginae, a group of canids endemic to North America from the early Miocene epoch through the Pliocene epoch 4.9-1.8 Mya. Two fossil specimens of Borophagus diversidens were measured by Legendre and Roth in 1988. They estimated that specimen one weighed 89 kg and the second weighed 75.4 kg.