The U.S. Fish and Wildlife Service (Service) published a final rule (pdf) in the Federal Register listing the Sierra Nevada yellow-legged frog (Rana Sierrae) and the northern distinct population segment (DPS) of the mountain yellow-legged frog (Rana muscosa) as endangered, and the Yosemite toad (Anaxyrus Canorus) as threatened. The agency proposed listing the species on April 25, 2013, following a decade of litigation intiiated by the Center for Biological Diversity, as describe in the proposed rule.
Recent research based on mitochondrial DNA, morphological information, and acoustic studies led the Service to recognize two distinct species of mountain yellow-legged frog in the Sierra Nevada. The Sierra Nevada yellow-legged frog occupies the western Sierra Nevada north of the Monarch Divide (in Fresno County) and the eastern Sierra Nevada (east of the crest) in Inyo and Mono Counties. The northern DPS of the mountain yellow-legged frog occupies the western Sierra Nevada from south of the Monarch Divide in Fresno County through portions of the Kern River drainage. The species' historical range is set out in Figure 1, in the final rule, reproduced here.
The Yosemite toad is a moderately-sized toad with a range that is predominantly on federal land. Its distribution extends from the Blue Lakes region north of Ebbetts Pass in Alpine County to just south of Kaiser Pass in the Evolution Lake/Darwin Canyon area in Fresno County. The species historically spanned elevations from 4,790 to 11,910 feet above sea level.