- Aleutian fox (Urocyon littoralis): This species of fox was found on the Aleutian Islands of Alaska and is believed to have gone extinct in the 18th or 19th century due to the introduction of non-native species and fur hunting.
- Channel Islands fox (Urocyon littoralis catalinae): This subspecies of the Island fox was found on Santa Catalina Island off the coast of California. It is believed to have gone extinct in the 1990s due to a combination of factors including habitat loss, predation by non-native species, and disease.