Today in the United States, including Hawaii, there are six species of iguana lizards. Two species, the desert iguana (Dipsosaurus dorsalis) and the Northern Chuckwalla are native to our desert Southwest, and are found in suitable habitats in Arizona, California, Nevada and Utah. The green iguana (Iguana iguana), and three species of spiny-tail iguanas are introduced species and may be encountered in the states of Florida, Texas, Arizona and Hawaii.
The Green Iguana is a large tree-dwelling lizard. The more widely distributed of the two species of iguana, the common or green iguana, is Iguana iguana. It is found in Latin America and on some of the Lesser Antilles Islands. Many green iguanas from Mexico and northern Central America bear marked hornlike nubbins on the snout.
The green iguana we are most familiar with as a pet is known as Iguana iguana. The iguana is “cold-blooded”, meaning that the body cannot generate sufficient body heat to sustain itself. It is dependent on the outside heat sources to raise its body temperature.
Iguanas hatch from eggs, and a single clutch may contain as many as 60 eggs. The average size of a newborn iguana is about 7 inches long. Within a year, it potentially can grow to a foot-and-a-half in length.
Listed below are some distinguishing body features of green iguanas:
- Femoral Pores
- On the underside of each back leg, iguanas have small, circular holes called femoral pores. Usually, the femoral pores of males are significantly larger than those of females. These pores produce a waxy substance that helps the male to mark its territory. In most green iguanas, the size of these pores is used to distinguish males from females.
- Subtympanic Scales
- Below the eardrum (tympanum) of all green iguanas there are one to three greatly enlarged scales.
- Parietal Eye
- Iguanas have a parietal eye. It is located between the eyes, but a little further toward the back of the head. This eye is sensitive to light, probably aiding in the breeding cycle.
- Iguanas have a short, thick tongue.
- Both male and female have a row of large pointy scales down the length of the spine and tail.
- The iguana has a large, hanging fold of skin under its throat called a dewlap. This is expanded and displayed in courtship and battle.
Iguanas are vegetarian reptiles throughout their entire life and have been known to eat up to 50 different types of plants. It is a strong swimmer. Iguanas require warmth, sunlight and humidity for good health. This is a pet that may live longer than a dog or cat, may attain a length of more than 6 feet and need a cage the size of a room, special diets and supplements.
You must also be aware that it is no longer an easy task to find a new home for a large iguana that has for one reason or other outgrown its welcome. Simply turning these cold-sensitive lizards loose is not a viable option and is illegal as well. In most cases, the only viable option is euthanasia.