Enhydrocyon is an extinct genus of bone crushing dog which inhabited North America exclusively during the Oligocene living from around 28.7—22.0 Ma (AEO) and existed for approximately 6.7 million years.
Enhydrocyon's dentition suggests this animal was a hypercarnivore or mesocarnivore. Enhydrocyon was a large and powerfully built carnivore with a short snout and deep jaws reminiscent of a jaguar. Macdonald describes Enhydrocyon as an evolution within the Canidae of a big cat-like carnivore.
†Enhydrocyon crassidens (24.4—22.7 Ma AEO). Type locality: Monroe Creek (American Museum of Natural History, Rosebud 12), Shannon County, South Dakota. Weight estimated to be 45-50 lbs. (Legendre & Roth).
†Enhydrocyon pahinsintewakpa (~24.5—23.3 Ma AEO). Type locality: Sharps SDSM V-5361 aka LACM 1983 (Sharps Formation), Shannon County, South Dakota. Weight was approximately 40-45 lbs. (John Alroy), (Legendre & Roth, S. Legendre and C. Roth. 1988. 
†Enhydrocyon sectorius (nomen vanum)
†Enhydrocyon stenocephalus (25.9—25.7 Ma (AEO). John Day Units G, H, I, and J., Wheeler County, Oregon. Weight 45-50 lbs. (Legendre & Roth).