Oxetocyon

Oxetocyon Temporal range:
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Family:	Canidae
Subfamily:	†Borophaginae
Genus:	†Oxetocyon Green, 1954
Species:	†O. cuspidatus
Binomial name
†Oxetocyon cuspidatus Green, 1954
Range of Oxetocyon based on fossil distribution

Oxetocyon ("beginning dog") is an extinct genus of the subfamily Borophaginae and a terrestrial canine which inhabited North America during the Whitneyan stage (33.3 Mya)—(30.8 Mya) of the Oligocene epoch. Oxetocyon existed for approximately 2.5 million years.

Taxonomy

The teeth of Oxetocyon indicate a more hypocarnivorous diet, as is found in the living raccoon dog, and suggest a potential relationship to the unusual borophagine Otarocyon. Oxetocyon is distinguished from Otarocyon by its own set of dental specializations for an omnivorous diet, particularly by the presence of a cleft that divides each upper molar into front and back halves.

Morphology

Fossil specimens of two individuals' body mass were examined by Legendre and Roth. The first specimen was estimated to weigh 1.04 kg (2.29 lbs). The second specimen was estimated to weigh 1.1 kg (2.44 lbs).

Species

Only a single species, O. cuspidatus, is known. Fossils of Oxetocyon are rare and, as a result, the genus is poorly known, and only the teeth, dentaries, and a fragmentary skull have been reported.

Sister genera

Archaeocyon, Otarocyon, and Rhizocyon.

Fossil distribution

• Roundhouse Rock, Brule Formation, Morrill County, Nebraska ~33.3—30.8 Ma.
• UNSM Sx-28, Brule Formation, Sioux County, Nebraska ~33.3—30.8 Ma.
• Brule Formation, Oglala Lakota County, South Dakota ~33.3—30.8 Ma.
• Harris Ranch Unit C, Brule Formation, Fall River County, South Dakota ~33.3—30.8 Ma.