Rio Fuerte beaded lizard in exhibit

Rio Fuerte Beaded Lizard

Scientific Name
Heloderma horridum exasperatum
Geographic Range:
Western Mexico
Small mammals, birds, lizards, frogs, insects, and eggs
Rio Fuerte beaded lizard Endangered Status Graph - Least Concern Endangered Status Graph - Least Concern

More Information

Rio Fuerte beaded lizards are a subspecies of Mexican beaded lizard with a long and heavy body. They can get to 35 inches in length and weigh up to 9 pounds. They are named for the hard brown and black scales on their back, which look like beads. They also have yellow scales.

Breeding season takes place between February and March. After that, females bury three to 13 eggs and abandon them, leaving young on their own after hatching. Survivors reach maturity at around 2.5 years of age.

Did You Know?

  • Mexican beaded lizards have several special grooved teeth that deliver venom when they bite. Those teeth are on the lower jaw bones. They use the venom primarily for defense but may also use it to subdue prey. This venom is rarely fatal to humans.
  • Their tails look thick and swollen. That’s because they store fat the lizards can draw upon when food is scarce.
  • These reptiles are nocturnal. They hide during the day in burrows, sometimes abandoned homes used by other animals and sometimes ones they dug. When they first emerge at night, they are slow and clumsy.


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