gila monster (hē`lə), venomous lizard, Heloderma suspectum, found in the deserts of the SW United States and NW Mexico. It averages 18 in. (45 cm) in length, with a large head, stout body, thick tail that acts as a food reservoir, and short legs with strong claws. Its skin is covered with beadlike scales. Its coloring is marbled, a combination of brown or black with orange, pink, yellow, or dull white. The lizard's movements are slow and clumsy. It feeds on young birds and mammals and on eggs. Because the neurotoxic venom is produced by glands in the lower jaw and the grooved teeth through which it passes are set far back in the mouth, venom does not always enter the wound when a victim is bitten. The gila monster must fix its teeth deeply in a certain position to give a fatal bite. The only other member of the genus Heloderma, the beaded lizard, H. horridum, is a somewhat larger black and yellow lizard, found in W Mexico. These two species are the only known lizards whose venom is fatal. They are classified in the phylum Chordata Chordata (kôrdā`tə,–dä`–)
..... Click the link for more information. , subphylum Vertebrata, class Reptilia, order Squamata, family Helodermatidae.

Gila monster

One of the only two species (both in the family Helodermatidae) of venomous lizards, named for the Gila River basin and found in the southwestern U.S. and northern Mexico. The Gila monster (Heloderma suspectum) grows to about 20 in. (50 cm) long, is stout-bodied with black and pink blotches or bands, and has beadlike scales. During warm weather, it feeds at night on small mammals, birds, and eggs and stores fat in the tail and abdomen for the winter. It is sluggish but has a strong bite. The venom (a neurotoxin) is conducted along grooves in the teeth from glands in the lower jaw. Bites are rarely fatal to humans. The other venomous species is the Mexican beaded lizard (H. horridum).

Gila monster

small but venomous lizard found in U.S. desert. [Zoology: NCE, 1084]

See : Deadliness