File Snakes: Acrochordidae

Also known as wart snakes or elephant-trunk snakes, the file snakes have baggy skin that lies in loose folds. The skin is covered with tiny scales and small, bristly outgrowths that make the skin seem quite rough. This rough skin looks rather like the surface of a file, and some say it also looks as if it is covered with small warts; it is the appearance of their skin that gives them the common name "file" snakes. Although for many years people thought that the little file snake was venomous (VEH-nuh-mus), or poisonous, and dangerous to humans, scientists now know that none of the three file snake species, or types, has a bite that can harm a person.

File snakes spend nearly their entire lives in the water. A file snake has both its eyes and its nostrils, or nose holes, located on the top of its short head, so it can breathe the air and see above the water surface while the rest of the body remains underwater. The nostrils also have little valves, or flaps, that can close up when the snake dips completely below the water's surface. The tail is somewhat flattened from side to side and helps the snake swim. Male and female file snakes look very much alike, except that the females have slightly larger heads, thicker bodies, and shorter tails. The tail on a snake is the part of the body that extends back from a slit on the belly. File snakes range in length from about 20 to 76 inches (0.5 to 2 meters). The little file snake is the smallest member of the family, averaging 20 to 28 inches (51 to 71 centimeters) in length but sometimes reaching 40 inches (1 meter). The Arafura file snake grows to about 67 inches (1.7 meters), and the Java file snake grows to 76 inches (2 meters).