Hesperocyon is an extinct genus of canids (subfamily Hesperocyoninae,family Canidae) 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 mya—31.0 Ma. (AEO). Hesperocyon existed for approximately 11.5 million years.