Range
Northern Mexico through southwestern United States to central Canada. Canada south as Manitoba and southeastern as Alberta; Mexico south to Aguascalientes and San Luis Potosi; United States east to western Minnesota and west to central Montana.
Habitats
Usually found in the lower, damper parts of shortgrass and tallgrass, prairies, desert mesquite, sandhills, and desert scrub. Commonly visit irrigation canals, flood plains of rivers, reservoirs, and flood plains of rivers where they breed. Males sit on the shoreline or latch on to plants to call females. Eggs and larvae develop in shallow, clear, water.
Identification
Skin has many small warts and upper surface relatively symmetrical pattern of large dark spots with light edges. Cranial crests, or hard ridges, prominent between eyes and come to hard lump on snout. Long parotid glands behind the eyes. One sharp-edged tubercle and one smaller dark-tipped tubercle commonly on underside of each hind foot. Average female up to 4.5 inches (11.4 cm) snout-vent length and adult male generally shorter at 3.7 inches (9.5 cm). During breeding season, males develop dark, loose throat skin and dark patches on the inner thumb. The expanded vocal sack can push upwards into face, and the breeding call is an extended trill or pulsating ringing. Larvae usually black and become pale with mottled brown and gray and eyes high on head with dorsal fin highly arched. Recently metamorphosed toadlets can be as small as 1 cm. Eggs usually in a single row encompassed by two-layered jelly to separate them from each other.
Learn more with Schechter Natural History's Guide to Reptiles and Amphibians