Horned lizard

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(Redirected from Horned Toad)

{{Taxobox | color = pink | name = Horned Lizards | image = Short Horned Lizard.jpg | image_caption = Short-horned Lizard | regnum = Animalia | phylum = Chordata | classis = Reptilia | ordo = Squamata | subordo = Sauria | familia = Phrynosomatidae | genus = Phrynosoma | genus_authority = Wiegmann, 1828 | subdivision_ranks = Species | subdivision = See text. }} Horned lizards (Phrynosoma) are a genus of the Phrynosomatidae family of lizards. The horned lizard is popularly called a "horned toad," "horny toad", or "horned frog," but it is neither a toad nor a frog. The popular names come from the lizard's rounded body and blunt snout, which give it a decidedly toad-like or frog-like appearance. (Phrynosoma literally means "toad-bodied.") The lizard's "horns" are not true horns, but modified spiney scales.

There are 14 species of horned lizards in North America, 8 of which are native to the United States. The largest-bodied and most widely distributed of the U.S. species is the Texas horned lizard (P. cornutum).

Horned lizards are morphologically similar to the Australian thorny devil (Moloch horridus), but are only distantly related. Though due to other unique similarities, such as being sit and wait predators and prey upon ants, these two are considered to be a great example of convergent evolution.

Horned lizards carry with them a wide variety of means to avoid predation. Their coloration generally serves as camouflage. When threatened, a horned lizard puffs up its body to cause its spiny scales to protrude, making it difficult to swallow. At least four species also have the ability to squirt an aimed stream of blood from the corners of the eyes for a distance of up to 3 feet. This not only confuses would-be predators, the blood is mixed with a noxious biochemical that is foul-tasting to wolves, coyotes, bobcats, and domestic dogs and cats.

About 70% of the horned lizard's diet is made up of harvester ants, though they supplement these with termites, beetles, and grasshoppers. In California, Texas, and other states, horned lizards are considered threatened, though none are on the federal endangered species list. The Texas horned lizard has declined in about 30% of its range, though there is some indication it may be making a comeback. Some California horned lizard species are also in decline. The decline is usually blamed on overuse of pesticides and the spread of non-native South American ants. In California, the introduced species is the Argentine ant. In Texas, it is both the Argentine ant and the Brazilian fire ant. Both species are highly aggressive, fiercely territorial, and eradicate harvester ant colonies, destroying the horned lizard's principal source of food.

Some Native American peoples regarded horned lizards as sacred. The animal is a common motiff in the art many Native Americans in the Southwestern U.S. and in Mexico.

The horned lizard is the state reptile of both Texas and Wyoming, and as the "horned frog," is the mascot of Texas Christian University (TCU).

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