Order Carnivores | Rank Genus | |
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Similar Cynodesmus, Enhydrocyon, Osbornodon, Hesperocyoninae, Leptocyon |
Mesocyon is an extinct genus of terrestrial carnivore within the family Canidae, subfamily Hesperocyoninae, which inhabited North America from the Early Oligocene to Early Miocene 38.9—20.6 Ma, existing for approximately 18 million years.
Contents

Though a carnivore, dentition suggests this animal was a hypercarnivore or mesocarnivore.
Taxonomy
Mesocyon was the most basal member of a clade that also includes the genera Cynodesmus, Sunkahetanka, Philotrox, and Enhydrocyon. Mesocyon was named by Scott (1890). It was synonymized subjectively with Enhydrocyon by Swisher (1982). It was assigned to Canidae by Scott (1890), Carroll (1988) and Stevens (1991).
Morphology

Two specimens were examined by Legendre and Roth with the first specimen'S mass being estimated at 7.4 kg (16.3 lbs). The second specimen's mass was estimated at 7.19 kg (15.8 lbs).
Fossil distribution

Fossils were uncovered on two sites in north central Oregon. Also, 10 other sites from southern California Colorado, southern Wyoming, and western Nebraska.

