Gila monster Gila monster The Gila monster ("Heloderma suspectum", ) is a species of venomous lizard native to the southwestern United States and northwestern Mexican state of Sonora. A heavy, typically slow-moving lizard, up to long, the Gila monster is the only venomous lizard native to the United States and one of only two known species of venomous lizards in North America, the other being its close relative, the Mexican beaded lizard ("H. horridum"). Although the Gila monster is venomous, its sluggish nature means it represents little threat to humans. However, it has acquired a fearsome reputation, and is sometimes killed despite
Southern alligator lizard the fact that the back and belly scales of these lizards are reinforced by bone, as they are in alligators. Three subspecies can be distinguished: the California alligator lizard ("E. m. multicarinata"), the San Diego alligator lizard ("E. m. webbii"), and the Oregon alligator lizard ("E. m. scincicauda"). The subspecific name "webbii" is in honor of Thomas Hopkins Webb (1801–1866) who was Secretary of the United States and Mexican Boundary Survey (1848–1855). The subspecific name "scincicauda" means "skink tail". The southern alligator lizard measures from 3 to 7 inches (7.3 - 17.8 cm) in snout-to-vent length (SVL). Including tail, it