Sonoran Desert Toad
Incilius alvarius
The largest native species of toad found in the United States, it can reach a total length of 7.5 inches. This is a very plump toad. It has olive green or brown leathery…
How to identify
The largest native species of toad found in the United States, it can reach a total length of 7.5 inches. This is a very plump toad. It has olive green or brown leathery skin with many tiny bumps and fewer small bumps, the latter of which are often darker in color. This toad is characterized by swollen, elongated parotid glands behind the eyes, and a conspicuous white wart at each corner of the mouth. It also has bulging glands on its front and hind legs, which are sometimes whitish. All of these glands secrete a potent toxin. It has horizontal pupils and noticeable brow ridges above the eyes. Ventrum is an unmarked cream color.
Range
Ranges throughout the southern half of Arizona, south into northwest Mexico, and slightly into southwest New Mexico and southeast California.
Habitat
This nocturnal, semi-aquatic species will tolerate desert and semi-desert habitats. It's often found near streams, canals, irrigation ditches, and under water troughs. This toad likes to breed in manmade bodies of water, such as reservoirs, and often hides inside rodent burrows.
Variations
Body color ranges from a deep seaweed green to olive to light brown. Skin bumps may be colored yellow to brown, or they may be the same color as the surrounding skin.
Similar species
Most likely to be confused with the red-spotted toad (*Anaxyrus punctatus*) or Arizona toad (*Anaxyrus microscaphus*), both of which overlap in range.
Name and etymology
Alvarius: Latin for belonging to the womb or belly.
At a glance
Range
Ranges throughout the southern half of Arizona, south into northwest Mexico, and slightly into southwest New Mexico and south…
Habitat
This nocturnal, semi-aquatic species will tolerate desert and semi-desert habitats. It's often found near streams, canals, ir…
Guide
Reptiles and Amphibians of North America
Range map
Approximate range. © Mapbox © OpenStreetMap