FaunaHub

Iguana

ReptileLizardWild

A green iguana (Iguana iguana) basking, showing its crest and dewlap.

Green iguana (Iguana iguana).

Image: Wilfredor, CC0, via Wikimedia Commons.

Overview

Iguanas are large lizards of the family Iguanidae, native to the Americas and the Caribbean. This page is a group-level overview; the green iguana (Iguana iguana) is used as a familiar reference. Green iguanas are among the largest lizards in their range, with a crest of spines, a prominent dewlap, and (despite their size and claws) a largely plant-based diet.

Habitat & Range

Green iguanas live in tropical forests and along waterways in Central and South America, spending much of their time in trees near water, into which they may dive to escape danger. They have also been introduced to parts of the United States and elsewhere, where they can become invasive. Other iguana species occupy deserts, rocky coasts, and islands. Habitat and range vary by species.

Diet

Adult green iguanas are largely herbivorous, feeding on leaves, flowers, and fruit, with diet varying by age and species. This page describes general feeding ecology and does not give pet feeding instructions or quantities, which are specialised and should follow qualified reptile-veterinary guidance.

Behavior

Iguanas are good climbers and, in the case of the green iguana, strong swimmers. Males can be territorial, using head-bobbing and dewlap displays. They bask to regulate body temperature, as reptiles rely on external heat. Large iguanas have sharp claws and a powerful tail and can defend themselves when stressed or cornered. Behaviour varies among the iguana species.

Human Interaction & Conservation

Iguanas are wild reptiles; green iguanas are also widely kept as exotic pets, but they grow large, live long, and have demanding care needs, so they are not casual pets. Introduced green iguanas are a problem in some regions. Some other iguanas, such as certain island species, are threatened. Conservation status varies by species and should be checked against current sources. This page is educational, not care or veterinary advice.

Appearance & Recognition

The green iguana is a large lizard with a row of spines along the back and tail, a large round scale on the cheek, and a prominent throat fan (dewlap) used in display and temperature regulation. Despite the name, colour varies from green to grey, orange, or bluish depending on age, region, and individual. Other iguanas differ — some are stocky desert or rock species. A long tail and strong claws are common features.

Similar Animals

Iguanas are lizards, related to the chameleon, gecko, and monitor lizard covered on FaunaHub, though they form their own family. Green iguanas are sometimes confused with other large lizards, but the dewlap, dorsal crest, and cheek scale are helpful clues.

More photos of the iguana

Close view of a green iguana's head, showing spines and a large jowl scale.

Head of a green iguana, showing the crest and large cheek scale.

Image: Ianaré Sévi, CC BY-SA 3.0, via Wikimedia Commons.

Frequently Asked Questions — Iguana

Are iguanas herbivores?
Adult green iguanas are largely herbivorous, eating leaves, flowers, and fruit. Diet can vary by age and species. This page describes general ecology rather than pet diets, which are specialised and should follow qualified reptile-veterinary guidance.
Do iguanas make good pets?
Green iguanas are commonly kept as exotic pets, but they grow large, are long-lived, and have demanding housing, heat, lighting, and diet needs, so they are not casual pets. This page is educational, not care advice; consult a qualified reptile veterinarian or specialist before keeping any reptile.
Why are iguanas a problem in some places?
Green iguanas introduced outside their native range, such as in parts of the United States, can become invasive, damaging vegetation and infrastructure and competing with native species. Their management is a regional wildlife issue.

Sources and further reading

Authoritative wildlife references used for general educational context. Conservation status should always be verified against current IUCN Red List data. External links open in a new tab.