REPTILIA: SQUAMATA: HELODERMATIDAE: Heloderma

Heloderma suspectum Cope

Gila monster

("Gila" is pronounced "hee-lah")

Photos & text by Dr. Robert Sprackland.

Range: Central Arizona south into nw. Mexico.

Diagnosis: A chunky lizard with a short blunt tail, a body covered in bead-like scales, and possessing pale markings on the head. Tongue dark.

Description:

Natural History: Gila monsters are secretive, largely crepuscular animals that inhabit arid desert terrain. Though ungainly in appearance, they can swim and climb quite well. This species is venomous and a bite should be treated by a professional physician.

Reproduction: Lays eggs.

Taxonomy & Relationships:  

This Gila monster was photographed in 1970. It was one of the animals
studied by Charles Bogert as part of his monographic work on venomous
lizards. This animal was still alive many years after Bogert retired. Photo
by Robert Sprackland at the American Museum of Natural History.

Variation:  There is considerable variation in pattern. However, the two subspecies recognized differ in the amount of light pigment present. The northern Gila monster has more light coloring than its southern cousin.

Additional Comments: Gila monsters have long been popular with zoo and terrarium keepers, in part because they are both large and easily tamed. However, the venom causes excruciating pain, and lizards hold on with a legendary "bulldog" grip. Gila monsters should only be handled with care, and then only by experienced reptile handlers.

Type Specimen:

Literature: Click on book to order

Bogert, Charles and Rafael Martin Del Campo. 1956. The Gila monster and its allies. Bulletin of the American Museum f Natural History 109:1-238. Reprinted and updated 1993 by the Society for the Study of Amphibians and Reptiles.

Campbell, Jonathan and William Lamar. 2004. The venomous reptiles of Western Hemisphere. Two volumes. Comstock Cornell University Press.

Campbell, Jonathan and William Lamar. 1989. The venomous reptiles of Latin America. Comstock Cornell University Press. ISBN:0-8014-2059-8. 

Loza, Erik. 2000. Notes on the natural history and captive husbandry of the Gila monster. Reptile & Amphibian Hobbyist 6(5):8-19.

Smith, Hobart. 1946. Handbook of Lizards: Lizards of the United States and of Canada. Comstock Publishing. ISBN: 0-8014-8236-4.

Sprackland, Robert. 1992 Giant Lizards. TFH Publications, Neptune, NJ.

Stebbins, Robert. 1985. A Field Guide to Western Reptiles and Amphibians, 2nd edition. Houghton Mifflin Co. ISBN: 0-395-38253-X.