horned lizard or horned toad, broad, flat-bodied lizards of the genus Phrynosoma, found in arid regions from extreme SW Canada to Guatemala. There are several species in the United States W of the Mississippi. The body is 3 to 5 in. (7.6 to 12.7 cm) long; it has a short, thin tail, a short neck, and short legs. There are spines on the head, sides, and back. Horned lizards are protectively colored, usually in dull grays and browns. They feed on insects, especially ants, and are often found buried in the sand, with only their heads exposed. In some species the female lays eggs; in others the eggs are incubated internally and the young are born alive. When alarmed, members of some species eject a thin stream of blood from the nictitating membrane of the eye for a distance of several feet. Horned lizards are classified in the phylum Chordata, subphylum Vertebrata, class Reptilia, order Squamata, family Iguanidae.

or horned lizard

Any of about 14 species of lizards of the genus Phrynosoma, family Iguanidae. They usually have daggerlike head spines (horns) and a flattened oval body with pointed fringe scales along the sides. Species range from about 3 to 5 in. (8 to 13 cm) long. They are found from British Columbia, Can., south to Guatemala and from the U.S. states of Arkansas and Kansas westward, usually in desert or semidesert sandy country. They eat mainly ants. They hide by changing their colour pattern and wriggling sideways into the sand until all but the head is covered. They may defend themselves by inflating the body quickly and (rarely) spurting blood from the eyes.

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