Guatemalan beaded lizard
Conservation Messaging Opportunities
Physical features
Guatemalan beaded lizards have a large, flat head and a cylindrical body with a thick, long tail where they store fat. The tail serves as an energy reserve and may appear thin if the lizard is starved. The tail is the largest part of the lizard and it can make up 50% of their entire weight.
They are sexually dimorphic but it can very difficult to tell male from female. The females can grow to be 29.9 inches and weigh up to 4.4 lbs. The males are slightly larger and they can grow up to 35.4 inches and weigh up to 8.8 lbs.
Large, hard, bead-like scales cover the top of their body while the underside is covered with softer scales.
They are mostly black and brown with yellow spots along their tail and neck. Juveniles have larger yellow spots.
Range and Habitat
Range – The Motagua Valley of southeastern Guatemala.
Habitat – Seasonally dry forest
Diet: Carnivore
Wild – Small mammals, bird and lizard eggs, nestling birds, and insects.
Zoo – Quail eggs, frozen day old chicks, frozen rats
Lifespan
Wild – unknown but likely up to 30+ years
Zoo – up to 50+ years
Reproduction
The Guatemalan beaded lizard breeding season is in September through December with egg laying in November through January.
Copulation lasts 30-60 minutes and about 2 months later the female will lay 3-13 eggs and deposit them in a burrow modified from a ground dwelling bird or a lizard.
Incubation takes approximately 6 months at 80F and the female does not stay with the eggs.
When the eggs hatch, hatchlings can be up to 8.0 inches long.
Conservation: Critically Endangered
Major Threats: Deforestation, deliberate killing by humans, agriculture, and the illegal pet trade.
There is an estimated 350 mature individuals left, although the total adult population size is unknown. The population is thought to be decreasing.
They were added to CITES I in June 2007, making it illegal to export them out of the country. Despite this, the species is still threatened by the illegal pet trade.
Negative local myths about the lizards cause the locals to kill them on sight. Organizations in Guatemala work to educate the public about them so they can conserve the species.
Zoo Atlanta has partnered with The Foundation for the Conservation of Endangered Species of Guatemala (FESGUA) for Project Heloderma. In an effort to preserve this species, Project Heloderma works to combat illegal trade, educate the local people, and purchase and protect the lizards’ habitat. Project Heloderma also strives to prevent the illegal killing and selling of the lizards by donating clothing, school supplies, and computers to the communities to help alleviate costs.
Interpretive Information
The Guatemalan beaded lizard is one of two lizards known to be venomous (the other being the Gila monster) and they have specialized teeth in the lower jaw to deliver the venom when they bite.
They survive high temperatures for long periods of time by becoming completely inactive, a behavior known as aestivating, and utilizing the fat reserves in their tail for energy.
They swallow their food whole, except for eggs, which are sometimes broken first.
Although venomous, bites are usually non-fatal to humans. In fact, there has never been a well documented case of a human dying from a Guatemalan beaded lizard bite.
Guatemalan beaded lizards have few natural predators other than humans.
References
Angeli, Stephen L. 2004. Beaded Dragon. Retrieved from http://www.helodermahorridum.com/article.pdf
Ariano-Sánchez, D., Muñoz-Alons, A., Marquez, L.C. & Acevedo, M. 2014. Heloderma horridum. The IUCN Red List of Threatened Species. Version 2014.2. Retrieved from www.iucnredlist.org
Protecting the Guatemalan Beaded Lizard. The Nature Conservancy. Retrieved from http://web.archive.org/web/20110105154521/http://www.nature.org/wherewework/centralamerica/guatemala/features/index.html
Stout, N. 2003. "Heloderma horridum", Animal Diversity Web. Retrieved from http://animaldiversity.ummz.umich.edu/accounts/Heloderma_horridum/v
Updated 2014