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

Common Name:
Gila Monster
Scientific Name:
Heloderma suspectum
Type:
Reptiles
Diet:
Carnivore
Group Name:
Lounge
Average Life Span In The Wild:
Up to 20 years
Size:
20 inches
Weight:
4 pounds
IUCN Red List Status:
Near threatened
Current Population Trend:
Decreasing

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.

Population Range

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.

Venom

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 resulted in a reported human death. Unlike snakes, which inject venom, Gilas latch onto victims and chew to allow neurotoxins to move through grooves in their teeth and into the open wound.

Behavior

Gilas are lethargic creatures that feed primarily on eggs raided from nests and newborn mammals. They may spend more than 95 percent of their lives in underground burrows, emerging only to feed and occasionally to bask in the desert sun. They can store fat in their oversized tails and are able to go months between meals.

Gila populations are shrinking due primarily to human encroachment, and they are considered a threatened species.

This photo was submitted to Your Shot, our photo community on Instagram. Follow us on Instagram at @natgeoyourshot or visit us at natgeo.com/yourshot for the latest submissions and news about the community.
This photo was submitted to Your Shot, our photo community on Instagram. Follow us on Instagram at @natgeoyourshot or visit us at natgeo.com/yourshot for the latest submissions and news about the community.
Photograph by Sean Robert Hanrahan, National Geographic Your Shot

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