Southern Rocky Mountain wolf

The southern Rocky Mountain wolf (Canis lupus youngi) is a possibly extinct subspecies of gray wolf found over southeastern Idaho, southwestern Wyoming, northeastern Nevada, Utah, western and central Colorado, northwestern Arizona and northwestern New Mexico. It is a light-colored, medium-sized subspecies closely resembling C. l. nubilus, though larger, with more blackish-buff hairs on the back.

As of 2005, it is considered a valid subspecies by MSW3, though it is classed as a synonym of C. l. nubilus by the United States Fish and Wildlife Service.

Wolves have reestablished in Idaho and Wyoming, however, Canis lupus youngi is probably extinct, as the wolves there, as of 2015, are of subspecies Canis lupus occidentalis.