An Online Guide to the Reptiles & Amphibians of the United States

Herpedia™.com is not a reference for keeping reptiles or amphibians in your home, nor is it a truely scientific type encyclopedia that covers all of the different biological difference between two subspecies (i.e. genetic differences).

Herpedia™.com leans more to listing and identifying the species & subspecies of every reptile and amphibian in the United States that have been recognized to date. Information such as the scientific name, distribution maps, photographs, and information pages for each that contain the size, general description, range, habitat, mating/breeding, etc.

 

Reptiles and Amphibians are both vertebrates, meaning they have backbones, and are collectively called herpetofauna, or "herps". They are found on every continent except Antarctica, but only reptiles can live in the ocean. Both groups are cold-blooded, meaning they can't regulate their body temperature internally and must rely on their environment to do so. For example, a turtle might warm itself in the sun, while a lizard might move in and out of cover to regulate its temperature.

Skin - Reptiles have dry, scaly skin that helps them retain moisture and protects them from predators. Amphibians have thin, moist, absorbent skin that often has mucus on it and needs to be kept moist.

Eggs - Reptiles lay eggs with a protective outer layer, such as a brittle or leathery shell, and usually fertilize them internally. Amphibians lay jellylike, see-through eggs in water, and usually fertilize them after laying them.

Life cycle - Most amphibians are born with gills and later develop lungs, and their young have gills to survive in water. They can live on land and in water, but only venture onto land when they are fully mature. Reptiles, on the other hand, are born with lungs and have adapted to live completely on dry land.

Hearts - Amphibians have three-chambered hearts, while all reptiles except crocodiles have three-chambered hearts with two atria and one ventricle.

Amphibians

There are two of the three major groups of amphibians present in the United States and they are represented by 319 species. They are the salamanders (including newts) (201 species) and the frogs & toads (118 species).

Salamanders resemble lizards in that they have slender bodies, long tails, distinct body regions, and usually front and hinds legs of nearly the same size. Like most amphibians, they have a moist scaleless skin. Salamanders lack the scales, claws, and external ear opening that are present in lizards.

Frogs and Toads are easily identified by their hind feet. True frogs have webbed toes, Tree frogs have toe pads and webbing, Toads have tubercles and no webbing, Spadefoot Toads have a horny projection (the spade) and no webbing.

 

Reptiles

There are some 476 species of native and introduced species of reptiles in the U.S. They are represented by Crocodilians (4 species), turtles (88 species), lizards (198 species), amphisbaenid (1 species), and snakes (185 species).

Crocodilians, with their size alone, are easily identified as the giants of the reptiles in the U.S. Their size, massive heads, protruding eyes and nostrils, and heavily muscular bodies, compressed tails distinguish them from their cousins, the lizards.

Turtles are recognized by everyone by their shells, which are generally used to distinguish species.

Snakes are the most specializes group of reptiles. They are distinctive in having a long scaled body. Unlike lizards, they have no arms or legs, external ear openings, or eyelids.

Lizards share characteristics with the crocodilians and snakes, but unlike the crocodilians they lack the size, and unlike snakes, they have arms, legs, eyelids, and external ear openings. Snakes and lizards have three types of scales: smooth, keeled, and granular.

And the single species of Amphisbaenid is found in Florida and has a long limbless body that resembles an earthworm. The body scales have formed into rings that encircle the body.