Gila monster
The Gila monster (Heloderma suspectum, HEE-lə) is a species of venomous lizard native to the southwestern United States and northwestern Mexican state of Sonora. A heavy, slow-moving lizard, up to 60 cm (2.0 ft) 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). Though the Gila monster is venomous, its sluggish nature means it represents little threat to humans. However, it has earned a fearsome reputation and is sometimes killed despite being protected by state law in Arizona.
Description, taxonomy and etymology
In this species, the largest extant lizard native to North America north of the Mexican border (non-natives like green iguanas are larger), snout-to-vent length is from 26 to 36 cm (10 to 14 in). The tail is about 20% of the body size and the largest specimens may reach 51 to 56 cm (20 to 22 in) in total length. Body mass is typically in the range of 350 to 700 g (0.77 to 1.54 lb), with 11 males having been found to average 468 g (1.032 lb). Reportedly, the very heaviest, largest specimens can weigh as much as 2,300 g (5.1 lb).