 Reptiles
Iguanas are well-proportioned lizards and most are typically "lizard-like" in appearance. They range in size from three inches to six feet long. The tail is usually longer than the body. They are almost totally restricted to the New World, except for two genera in Madagascar and one genus in Polynesia. They may be insectivorous, carnivorous, herbivorous or omnivorous depending upon the species and stage of life. The majority lay eggs that are soft-shelled and buried underground. They are found in habitats ranging from tropical forests to deserts and even along the seashore.
Crests, helmets and gular pouches occur in a variety of forms. These are usually more strongly developed in the males than in females. They play a significant part during courtship and in rivalry fighting. Some iguanas are able to display physiological color changes that are as well developed as the members of Chameleonidae.
Locally, the lizard we call a "chameleon" is actually a member of the iguanid family. Anolis carolinensis, or green anole, is its proper name. They are four to eight inches long. They are slender and the body color is usually green or brown often with patterns of darker spots (rarely stripes). The adhesive lamellae on the ventral surface of the toes and fingers allow them to run along smooth surfaces, even glass. They have a large throat sac. They do have the ability to change color. They eat a variety of arthropods, so they are beneficial in reducing insects around your home.
Iguanas in the genus Brachylophus are called Fiji iguanas. There are two species. They inhabit tropical forest. These may reach a length of 35 inches. Females are uniformly green and males are blue-green with darker or lighter crossbands. They are tree dwellers and consume plants and occasionally crickets. San Antonio Zoo exhibits Fiji Island banded iguana (Brachylophus fasciatus), pictured above. This species is endangered due to deforestation.
The chuckwalla belongs to the genus Sauromalus. The seven species are found in the southwestern United States and northern Mexico where they inhabit rocky semideserts and steppes. They may attain a length of 17.5 inches. The body is plump and strongly flattened dorso-ventrally with skin folds along the sides. The skin is rough. These lizards are mainly herbivorous and are diurnal (day active). The San Antonio Zoo exhibits Sauromalus obesus.
The six species in the genus Oplurus are found in dry, rocky regions of Madagascar. They have large, rough spinous scales on the tail. They reach a length of 9.75 inches. Some species are tree-dwellers and some are ground-dwellers. Their diet is primarily arthropods. The San Antonio Zoo has Cuvier's iguana (Oplurus cuvieri).
|
