Philotrox is an extinct monospecific genus of the Hesperocyoninae subfamily of early canids native to North America. It lived during the Oligocene, 30.8âÂÂ26.3 Ma, existing for approximately . In form, it was intermediate between the small Cynodesmus and the later Enhydrocyon, the first hypercarnivorous, "bone-cracking", canid.