In general, these snakes are an average length of around 30 inches, but specimens of the Western in excess of 54 inches (MORE)
The fauna of the United States of America is all the animals living in the Continental United States and its surrounding seas and islands, the Hawaiian Archipelago, Alaska in the Arctic, and several island-territories in the Pacific and in the Caribbean. The U.S. has arguably the most diverse fauna in the world and has many distinctive indigenous species found nowhere else on Earth. With most of the North American continent, the U.S. lies in the Nearctic faunistic realm, a region containing an assemblage of species similar to Northern parts of Africa and Eurasia. An estimated 432 species of mammals characterize the fauna of the continental U.S. More than 800 species of bird and there are more than 100 000 known species of insects. There are 311 known reptiles, 295 amphibians and 1154 known fish species in the U.S. Known animals that exist in all of the Lower 48 include white-tailed deer, bobcat, raccoon, muskrat, striped skunk, barn owl, American mink, American beaver, North American river otter and red fox.
Huge parts of the most beautiful parts of the country with the most distinctive indengious wildlife are protected as national parks. In 2013, the U.S. has more than 6770 national parks or protected areas, all together more than 2,607,131 km2. The first national park was Yellowstone National Park in the State of Wyoming, established in 1872. Yellowstone National Park is widely considered to be the finest megafauna wildlife habitat in the U.S. There are 67 species of mammals in the park, including the gray wolf, the threatened lynx, and grizzly bears. Herpetology
Agkistrodon piscivorus is a venomous snake, a species of pit viper, found in the southeastern United States. Adults are large and capable of delivering a painful and potentially fatal bite. When antagonized, they will stand their ground by coiling their bodies and displaying their fangs. Although their aggression has been exaggerated, on rare occasions territorial males will approach intruders in an aggressive manner. This is the world's only semiaquatic viper, usually found in or near water, particularly in slow-moving and shallow lakes, streams, and marshes. The snake is a strong swimmer and will even enter the sea, successfully colonizing islands off both the Atlantic and Gulf coasts.
The generic name is derived from the Greek words ancistro (hooked) and odon (tooth), and the species name comes from the Latin piscis (fish) and voro (to eat); thus, the scientific name translates into “hooked-tooth fish-eater”. Common names include variants on water moccasin, swamp moccasin, black moccasin, cottonmouth, gapper, or simply viper. Many of the common names refer to the threat display, where this species will often stand its ground and gape at an intruder, exposing the white lining of its mouth. Three subspecies are currently recognized, including the nominate subspecies described here. Its diet consists mainly of fish and frogs but is otherwise highly varied and, uniquely, has even been reported to include carrion.
Agkistrodon piscivorus leucostoma is a venomous pitviper subspecies found in the south central United States. It is the smallest of the three subspecies and tends to be darker in color.
Agkistrodon contortrix laticinctus is a venomous pitviper subspecies found in the southern United States, from Kansas, through Oklahoma and throughout central Texas.