Blainville's Horned Lizard

The San Diego horned lizard or the Blainville's horned lizard (Phrynosoma blainvillii) is a flat bodied lizard with long spiky horns located on the top and side of its head and has smaller spikes throughout its body and tail. The length of an adult size lizard can range from 2.5 to 4.5 in (6.4 to 11.4 cm) measure from the tip of its snout to its bottom just before where the tail starts. They are either red, brown, yellow or gray in color and have several black spots on their back and neck. These lizards have highly variable dorsal coloration but it usually matches the "prevailing soil color." The difference between males and females is that the female lizards are bigger than the males. The males also have bigger horns on the base of their tails and have noticeable pores on the interior of their hind legs.

This species ranges from the Central Valley of California south through Southern California to northern Baja California.

These lizards are usually found near mountains in areas that are sandy, with low vegetation and near ant hills. Populations of Blainsville's horned lizard have been identified at elevations ranging from 10 m (33 ft) above sea level (El Segundo Dunes, Los Angeles County) to approximately 2,130 m (6,990 ft) above sea level (Tahquitz Meadow, Riverside County).

Their diet is mostly harvester ants, but they do eat spiders, beetles, termites, and other insects. Harvester ants require dry conditions and therefore struggle in cultivated urban ecosystems with irrigated lawns, which in turn impacts horned lizard populations.