Protocyon

Protocyon is an extinct genus of large canid endemic to South and North America during the Late Pleistocene living from 781 to 12thousand years ago.

Description
Protocyon was a hypercarnivore, suggested by its dental adaptations. Like many other large canids, it was most likely a pack hunter. It hunted the medium-sized grazers and browsers, and bite marks on fossils suggest that it may have hunted Glyptotherium. The find of a molar tooth found in Santa Vitória do Palmar in Brazil suggests a weight of between 25 and 37 kg for this particular specimen. , modest in size compared to other canids including the dire wolf. However, despite its size, isotopic analysis shows a dietary overlap with Smilodon populator, which implies it might actively hunt much larger prey animals since S. populator weighed at least 400kg.

Taxonomy
Protocyon was named by Giebel in 1855 and assigned to Canidae by Carroll in 1988. A member of the Cerdocyonina lineage, its closest living relative might be the bush dog.

Palaeobiology
In contrast to its contemporary carnivores S. populator and Arctotherium wingei, dental stable isotope evidence shows Protocyon troglodytes in the Brazilian Intertropical Region (BIR) had a preference for open savanna environments.

Fossil distribution
Fossils of Protocyon have been found in the Ñuapua and Tarija Formations of Bolivia, the Vorohue Formation of Buenos Aires, Argentina, Santa Elena Peninsula of Ecuador, Sopas Formation of Uruguay, Mene de Inciarte Tar Seep of Venezuela and various sites in Brazil, among others the Jandaíra Formation.

Canid fossil material from the Hoyo Negro pit in the Sac Actun cave system (Mexico), initially identified as remains of a coyote, was reinterpreted as remains of P. troglodytes by , indicating that this taxon was also present in the southern part of North America.