Hesperocyonines

Hesperocyon is an extinct genus of canids belonging to the subfamily Hesperocyoninae of the canid family that was endemic to North America, ranging from southern Canada to Colorado. It appeared during the Uintan age, –Bridgerian age (NALMA) of the Mid-Eocene– 42.5 Ma to 31.0 Ma. (AEO). Hesperocyon existed for approximately .

The extinct Hesperocyoninae are one of three subfamilies found within the canid family. The other two canid subfamilies are the extinct Borophaginae and extant Caninae.

Cynodesmus ("dog link") is an extinct genus of omnivorous canine which inhabited North America during the Oligocene living from 33.3—-26.3 Ma and existed for approximately .

Mesocyon ("middle dog") is an extinct genus of the Hesperocyoninae subfamily of early canids native to North America. It lived from the Oligocene to Early Miocene, 30.3—20.3 Ma, existing for approximately . Fossils are known from Oregon, southern California and the northern Great Plains. It was roughly coyote-sized, and the first known canid to have a primarily meat-based diet.

Sunkahetanka is an extinct monospecific genus of the Hesperocyoninae subfamily of early canids native to North America. It lived during the Oligocene, 30.8—26.3 Ma, existing for approximately . In form, it was intermediate between the small Cynodesmus and the later Enhydrocyon, the first hypercarnivorous, "bone-cracking", canid.

Caedocyon ("fit for cutting dog") is an extinct monospecific genus of bone crushing canid which inhabited western North America during the Oligocene 30.8—20.6 Ma, existing for approximately .

Ectopocynus ("strange dog") is an extinct genus of bone crushing canid which inhabited North America from the Oligocene to the Early Miocene. It lived from 33.3 to 16.0 Ma and existed for approximately .

Osbornodon ("Osborn's tooth") is an extinct genus of canid that were endemic to North America and which lived from the Oligocene to the Early Miocene, 33.9—15.97 Ma (AEO), existing for approximately . It was the last surviving genus of the hesperocyonine subfamily, the oldest subfamily of canids. The genus is named for Henry Fairfield Osborn. ==Species== Seven known species of Osbornodon existed: Osbornodon brachypus Cope 1881 Osbornodon fricki Wang 1994 (18 Ma) Osbornodon iamonensis Sellards 1916 (21 Ma) Osbornodon renjiei Wang 1994 (33 Ma) Osbornodon sesnoni Macdonald 1967 (32 Ma) Osbornod

Philotrox is an extinct monospecific genus of the Hesperocyoninae subfamily of early canids native to North America. It lived during the Oligocene, 30.8—26.3 Ma, existing for approximately . In form, it was intermediate between the small Cynodesmus and the later Enhydrocyon, the first hypercarnivorous, "bone-cracking", canid.

Enhydrocyon is an extinct genus of bone crushing canid which inhabited North America during the Oligocene and Early Miocene, 30.8—20.4 Ma, existing for approximately .