The relict leopard frog (Lithobates onca) is a species of frog in the family Ranidae, endemic to the United States. It is found along the Colorado river in extreme northwestern Arizona, and adjacent Nevada and southwestern Utah, although its present range seems to be restricted to the Lake Mead National Recreation Area. Its natural habitat is freshwater springs and their outlets. It is threatened by habitat loss to agriculture and water development as well as invasive species. References External links Rana onca recordings Lithobates Amphibians described in 1875 Amphibians of North America Amphibians of the United States Endemic fauna of the United States Taxonomy articles created by Polbot