Sonoran Desert toad

Arizona’s largest toad, Sonoran Desert toads grow to 7.5 inches or more in length. They resemble frogs in that they have relatively smooth, typically olive-green/brown skin, but they can be identified as toads by the crests on the head (cranial crests), and prominent, elongated glands on both sides of the back of the head (parotoid glands) and on the hind legs. Young toads have small dark, orange-tipped spots on the back. Larger tadpoles are gray or brown with a rounded tail tip, and grow to about 2.25 inches. (information from http://www.reptilesofaz.org/ )