A reticulated Gila monster (<i>Heloderma suspectum suspectum</i>), a subspecies of Gila monster, photographed at Gladys Porter Zoo in Brownsville, Texas
A reticulated Gila monster (Heloderma suspectum suspectum), a subspecies of Gila monster, photographed at Gladys Porter Zoo in Brownsville, Texas
Photograph by Joel Sartore, National Geographic Photo Ark

Gila Monster

At a length of up to two feet and a maximum weight exceeding five pounds, the venomous Gila monster (pronounced HEE-luh) is the largest lizard native to the United States.

Easily identified by their black bodies marked with dramatic patterns of pink, orange, or yellow, Gilas are found in the Mojave, Sonoran, and Chihuahuan deserts of the southwestern U.S. and northwestern Mexico. They take their name from Arizona's Gila River basin, where they were first discovered.

The Gila monster is one of only a handful of venomous lizards in the world. Others include the similar-looking Mexican beaded lizards, as well as iguanas and monitor lizards. Its venom is a fairly mild neurotoxin. And though a Gila bite is extremely painful, none has

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