The Yosemite toad (Anaxyrus canorus, formerly Bufo canorus) is a species of true toad in the family Bufonidae. Endemic to the Sierra Nevada of California, the species ranges from the Alpine County to Fresno County. Yosemite toads are only found in the montane to subalpine elevational zone of asl. The Yosemite toad is similar to the nearby Western toad, but in many ways adapted to a high elevation lifestyle. It was initially described during the Grinnell Survey of California, by an undergraduate student of Joseph Grinnell named Charles Camp. Description Adults Yosemite toads are medium-sized (48–84 mm SVL) stocky toads, with females averaging larger than males. They generally lack cranial crests, but males will rarely have weakly developed ones. Their eyes have a dark brown iris with gold iridophores. In comparison with the closely related Western toad (A. boreas), the parotoid glands are large, narrowly spaced, and irregularly shaped (oval or flattened), less than one gland width apart. Like the parotoids, the eyes are spaced narrowly apart, usually less than the width of the upper eyelid. The warts are large, smooth, and the dorsal skin between warts is smooth as compared to the Western toad. It is the most sexually dichromatic species of anuran in North America, with males and females displaying strikingly divergent patterns and coloration at maturity. Females are dorsally covered in black blotches that have white or cream borders, with a tan, copper, or ruddy background; males are more uniformly colored, ranging from yellow-green, to olive drab, to greenish brown, sometimes with scattered black flecks near warts. Juveniles resemble adult females, except with a thin mid-dorsal stripe, which gradually fades during development (faster in males than females). A prominent mid-dorsal stripe is lacking in this species, unlike the Western toad. As juvenile males mature, their black blotches shrink and ultimately disappear, whereas they expand and reticulate in developing females. Unlike other members of the A. boreas species group (A. boreas, A. nelsoni, A. nestor [extinct], A. canorus, and A. exsul), Yosemite toad males have a vocal sac and produce an advertisement call to attract females during breeding. The call is a high-pitched, melodious, flute-like trill repeated frequently. Charles Camp chose the specific epithet "canorus" (meaning tuneful) for the species based on its advertisement call. The trill contains 26–51 evenly spaced notes that last an average of 2.6 seconds. Eggs Eggs are darkly pigmented and laid in 1