Sonoran Desert Toad, Colorado River Toad

You won't have any trouble identifying B. alvarius. It is the largest native North American species of toad. In terms of snout-to-vent length, B. alvarius requires a minimum of three inches for sexual maturity, although breeding adults continue to grow up to seven inches in length. This desert dweller is of stout build with a squat body and a flat broad head. The skin is smooth and leathery, sparsely covered with pale orange warts, and can change considerably from a dark brown to olive or grayish green. The belly is cream colored and usually unmarked. There are one to four prominent round white warts at the corner of the mouth. But, by far, the most identifying characteristic of B. alvarius is the presence of large granular glands on the neck and limbs.