Mexican Beaded Lizard

Mexican Beaded Lizard

Reptiles

SCIENTIFIC CLASSIFICATION

COMMON NAME: Mexican beaded lizard, beaded lizard
KINGDOM: Animalia
PHYLUM: Chordata
CLASS: Reptilia
ORDER: Squamata
FAMILY: Helodermatidae
GENUS SPECIES: Heloderma (studded skin) horridum (rough or horrible) exaspertatum (rough)

FAST FACTS

DESCRIPTION: The stripes and spots (white to yellow in color) on its black bumpy skin give this lizard a beaded appearance and its name. It has a thick, fleshy tail that is slightly shorter than the rest of the body, and short powerful limbs.
SIZE: 32.5-45 cm (13-18 in.) adult average length
WEIGHT: 2.3-2.7 kg (5-6 lb.) adult average
DIET: Primarily consists of eggs, young birds, mammals, and reptiles
INCUBATION: 28-30 days; young are able to survive without parental support
SEXUAL MATURITY: 2-3 years
LIFE SPAN: In excess of 30 years
RANGE: Southwestern United States; northern and southwestern Mexico to northern Guatemala
HABITAT: The lizard inhabits desert scrub and tropical thorn woodlands. Beaded lizards spend as much as 98% of their lives underground.
POPULATION: GLOBAL No data
STATUS: IUCN Vulnerable
CITES Appendix II
USFWS Not listed

FUN FACTS

1. The Mexican beaded lizard and its close relative, the gila monster (Heloderma suspectum), are the only two venomous lizards in the world. They possess venom glands in their lower jaws. The venom is delivered by capillary action along grooved teeth. In essence, they chew the venom into their prey. There is no anti-venom for the beaded lizard bite.
2. While they are at home in the desert, beaded lizards actually need a higher humidity than other desert reptiles.
3. Although beaded lizards appear sluggish, they are able to move rapidly when provoked. They can also produce a hissing sound to warn off intruders.
4. When food is scarce, the lizard metabolizes fat stored in its tail.

ECOLOGY AND CONSERVATION

Beaded lizards play a pivotal role in the desert ecology of the American southwest. By feeding on the eggs or young of small desert inhabitants, beaded lizards help control their populations. As with any small carnivore, venomous or not, they are preyed on extensively by larger predators.

BIBLIOGRAPHY

Gotch, A.F. Reptiles, Their Latin Names Explained. New York: Blandford Press, 1986.

Mattison, Chris. Lizards of the World. New York: Facts on File, Inc., 1989.

Rogner, Manfred. Lizards. Vol. 2. Malabar, Florida: Krieger Publishing Co., 1994.