Heloderma horridum


Taxonomy [top]

Kingdom Phylum Class Order Family

Scientific Name: Heloderma horridum
Species Authority: (Weigmann, 1829)
Common Name/s:
English Beaded Lizard
French Héloderme granuleux, Héloderme horrible
Spanish Escorpión, Lagarto de Cuentas
Trachyderma horridum Weigmann, 1829

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2007
Date Assessed: 2007-03-01
Assessor/s: Canseco Marquez, L. & Muñoz, A.
Reviewer/s: Cox, N., Chanson, J.S. & Stuart, S.N. (Global Reptile Assessment Coordinating Team)
Listed as Least Concern in view of its wide distribution, presumed large population, it occurs in a number of protected areas, and because it is unlikely to be declining fast enough to qualify for listing in a more threatened category.
1996 Vulnerable
1994 Indeterminate (Groombridge 1994)
1990 Indeterminate (IUCN 1990)
1988 Indeterminate (IUCN Conservation Monitoring Centre 1988)
1986 Indeterminate (IUCN Conservation Monitoring Centre 1986)

Geographic Range [top]

Range Description: This species is found in at low to moderate elevations in the Pacific foothills of Mexico from southern Sonora to Chiapas, and along the Pacific drainages in southeastern Guatemala (Departamento de Santa Rosa). It has an elevational range of around 400 to 1,000 m asl.
Guatemala; Mexico
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: It appears to be an uncommon species.
Population Trend: Unknown

Habitat and Ecology [top]

Habitat and Ecology: This lizard is most regularly encountered in tropical deciduous forest, but can also be found in thorn forest, tropical scrubland, and low elevation oak forest. It does not seem to be present in disturbed areas.
Systems: Terrestrial

Threats [top]

Major Threat(s): In general, the species is threatened by various forms of deforestation and by human persecution.

Conservation Actions [top]

Conservation Actions: This species is protected by Mexican law under the category A (Threatened), and it has been recorded from several protected areas. In Guatemala it is protected by national legislation, with part of the species range within protected areas. It is listed on Appendix II of CITES. Heloderma horridum charlesbogerti is listed on CITES Appendix I. Additional research is needed into the taxonomic status, distribution and threats to this species.

Bibliography [top]

Ariano-Sánchez, D. 2006. The Guatemalan beaded lizard: endangered inhabitant of a unique ecosystem. Iguana 13(3): 178-183.

Baillie, J. and Groombridge, B. 1996. 1996 IUCN Red List of Threatened Animals. International Union for Conservation of Nature, Gland, Switzerland.

Beck, D.D. and Lowe, C.H. 1991. Ecology of the beaded lizard, Heloderma horridum, in a tropical dry forest in Jalisco, Mexico. Journal of Herpetology 25(4): 395-406.

Campbell, J.A. and Lamar, W.W. 1989. The venomous reptiles of Latin America. Cornell University Press, Ithaca, New York.

Campbell, J.A. and Vannini, J.P. 1988. A new subspecies of Beaded Lizard, Heloderma horridum, from Motagua Valley of Guatemala. Journal Of Herpetology 22(4): 457-468.

DeGraaf, R.M. and Rudis, D.D. 1983. Amphibians and Reptiles of New England: Habitats and Natural History. University of Massachusetts Press, Amherst, Massachusetts.

Groombridge, B. (ed.). 1994. 1994 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland and Cambridge, UK.

IUCN. 1990. 1990 IUCN Red List of Threatened Animals. Gland, Switzerland and Cambridge, UK.

IUCN. 2007. 2007 IUCN Red List of Threatened Species. Available at: (Accessed: 12th September 2007).

IUCN Conservation Monitoring Centre. 1986. 1986 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland and Cambridge, UK.

IUCN Conservation Monitoring Centre. 1988. 1988 IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland and Cambridge, UK.

Köhler, G. 2003. Reptiles of Central America. Herpeton, Germany. 368 pp.

Platt, D.R. 1969. Natural history of the hognose snakes Heterodon platyrhinos and Heterodon nasicus. University of Kansas Publications, Museum of Natural History 18: 253-420.

Citation: Canseco Marquez, L. & Muñoz, A. 2007. Heloderma horridum. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <>. Downloaded on 17 April 2014.
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