ADDER

Puff adder (Bitis arietans) any of several venomous snakes of the viper family, Viperidae, and the death adder, a viperlike member of the cobra snake family, Elapidae. The name adder may also be applied to certain other snakes, such as the hognose snake (q.v.), a harmless North American species. Among the adders of the viper family are included the common adder (Vipera berus), the puff adders (several species including Bitis arietans; see photograph), and the night adders (four species of Causus). The common adder, or European viper, the serpent often mentioned in works of literature, is a stout-bodied snake that is widely distributed across Europe and Asia, even ranging north of the Arctic Circle in Norway. It grows to a maximum length of approximately 80 cm (30 inches) and is usually gray with a black zigzag band on the back and black spots on the sides. The common adder eats lizards and small mammals. Six to 20 young are born in August or early September. Its bite is rarely fatal to humans. The puff and night adders are terrestrial African vipers. The puff adder (so named because it gives warning by inflating its body and hissing loudly) is a large, extremely venomous snake found in the semiarid regions of Africa and Arabia. It is about 1 to 1.5 m (3 to 5 feet) long and is gray to dark brown with thin yellow chevrons on its back. A thick-bodied snake with a potentially lethal bite, it tends to stay put, rather than flee, when approached. Night adders are small, relatively slender vipers found south of the Sahara. They are gray with darker blotches, up to approximately 1 m long, and are characterized by small fangs and a relatively weak venom that is unlikely to cause more than pain and swelling in humans. Two of the four species, C. rhombeatus and C. resimus, have long venom glands that extend back from the head into the body cavity. The death adder (Acanthophis antarcticus) is found in Australia and nearby islands, though not in Tasmania, in a variety of habitats. The desert death adder, A. pyrrhus, is found only in the deserts and ranges of central and Western Australia. Although death adders are related to the slender-bodied cobras, they are viperlike in appearance, with thick bodies, short tails, and broad heads. They are about 45 to 90 cm (18 to 35 inches) long and are gray or brownish with darker crosswise bands. The death adder is a dangerous snake that has a potent venom that can cause death in about one-half of untreated cases.