A member of the crocodile family, alligators are living fossils that can be traced back 230 million years.
First listed as an endangered species in 1967, the American alligator was removed from the endangered species list in 1987 after the U.S. Fish and Wildlife Service pronounced a complete recovery of the species.
Population: Once on the brink of extinction, well over a million alligators can be found today in Florida, Louisiana, Texas, and Georgia.
Threats: Once hunted for their hides, alligators today are threatened mainly by habitat loss and encounters with people.
Survival: Alligators can live 35 to 50 years in the wild. In captivity, 60 to 80 years.
Order: Crocodilia, Family: Crocodylidae
The saltwater crocodile is most commonly found on the coasts of northern Australia, and the islands of New Guinea and Indonesia. It ranges west as far as the shores of Sri Lanka and eastern India, all along the shorelines and river mouths of Southeast Asia to central Vietnam, around Borneo and into the Philippines, and even out to Palau, Vanuatu, and the Solomon Islands. Saltwater Crocodiles are strong swimmers and can be found very far from land.
Order: Crocodolia, Family: Crocodylidae
Average weight: between 600 and 2,000 pounds.
Nile crocs are characterized by their lizard-shaped bodies and scaly hides.
Coloring: ranges from drab green or brownish to a blackish tone on the dorsal side, much lighter on the ventral side.
The eyes and nostrils of crocodiles are situated on the top of the head so they can see and breathe while the rest of their body remains almost totally underwater.
In the water, crocs have large, oar-like tails that they use to swim. Only their rear feet are webbed, and they are rarely used in movement underwater.
Order: Crocodylia, Family: Gavialidae
The gharial's most distinguishing feature is its long, narrow, slender snout, which makes for a useful fishing tool.
Its eyes are set well up on its head, and its nostrils are at the tip of its long, slender snout. The gharial's jaws have small, sharp teeth. The upper surface of its neck and back have an armor of bony plates, and the toes on its hind feet are webbed.
An average adult gharial measures up to 20 feet in length.
The gharial is olive green, mottled with chrome yellow, which fades with age. Its underside is pale yellow.
Order: Crocodilia, Family: Alligatoridae
The caiman is small in comparison to other lizard species.
It has a short tail and a short, smooth head with a high skull and upturned snout. They also have a pronounced overbite.
Their irises are generally brown but can take on greenish tinge.
Juveniles are brown with banding; adults have chocolate brown heads, and their jaws are flecked with white bands.
Caimans closely resemble alligators except for the small bony scales embedded in the skin of their belly.