Size up to 6 feet.

It has characteristic loud buzzing rattler sound.

Their venom contains at least two poisonous, protein-based substances. One, a neurotoxin, depresses the action of the heart and lungs; the other, a hemotoxin, damages blood vessels and other tissue.

 Rattlesnakes feed on small mammals and reptiles. Like most pit vipers, they give birth from eggs hatched inside the mother.

It has forked tongue. The snake uses this to "taste" the air and find its prey. Pit vipers, like the diamondback, also use heat sensitive areas in "pits" on the front of their heads to locate their victims even in total darkness.

Rattle snakes are recognized by a loose, horny rattle at the end of the tail, which is shaken vigorously to warn off intruders. The rattle is formed when the snake’s skin is shed,  the end section of the rattle and an attached ring of the old skin are retained on molting. A new ring is added each time the snake molts, which may be as often as four times a year. The last ring on the rattle often becomes worn and breaks off, so that the number of rattles is not, as popularly believed, an accurate indication of age of the snake

WATER MOCCASIN OR COTTONMOUTH   WATER MOCCASIN Water moccasin or cottonmouth, common name for a poisonous aquatic snake, one of the pit vipers of the viper family. It is called cottonmouth because the lining of its mouth is white. It lives in swamps. It is a slow-moving snake with hollow fangs that inject a toxin destructive to red blood cells. The bite, however, is rarely fatal, although it is painful and can cause local tissue damage. Brown or olive, with broad black bands across its body, the water moccasin averages 1.2 m (4 ft) in length. It feeds on fish and amphibians. CORAL Snake     Venom - Neurotoxic CORAL SNAKE Brightly colored venomous snakes of the cobra family. Coral snakes do not strike, but when touched they bite repeatedly, injecting a deadly poison that acts on the nervous system. The snakes are marked with a pattern of brightly colored rings or bands that are black, yellow, and red. About 40 species of coral snakes are known, most of them native to Central and South America.