|Named By:||Edward Drinker Cope in 1873|
|Time Period:||early to middle Miocene 20.43-13.6 Ma|
|Location:||Across North America|
|Size:||About 1.2 meters long|
|Classification:||| Chordata | Mammalia | Carnivora | Canidae | Borophaginae ||
|Also known as:||| Aelurodon francisi | Aelurodon simulans ||
Tomarctus is a canid genus of the extinct subfamily Borophaginae which inhabited most of North America during the late Early Miocene to the Early Barstovian age of the Middle Miocene (23--16 million years ago). Tomarctus existed for approximately 6.83 million years.
This animal shared a period and ecology with a variety of other bear dogs like the giant mustelid genus of bone-crushing canidae, Cynarctoides. As the bear dogs and giant mustelids became extinct, Tomarctus further radiated to fill a line of dogs which filled the hyena-like fruit eating and bone-crushing niches.