vampire bat, name for the blood-drinking bats of the family Desmodontidae, found in the New World tropics. Vampire bats feed exclusively on the blood of living animals and are thus the only true parasites among mammals. There are three species ranging from Argentina to N Mexico. They are small (about 3 in./7.5 cm long), round-bodied bats with large, pointed ears and naked snouts. Unlike most bats, vampire bats can walk on all fours with the body lifted off the ground; it is in this manner that they approach their sleeping prey. The bat uses its razor-sharp incisors to make a neat incision, usually without waking the victim, then laps the blood with its tongue. Its saliva contains an anticoagulant that causes the wound to seep for several hours. Vampire bats parasitize a variety of animals, chiefly mammals. Although the quantity of blood they take is insufficent to harm a large animal, they are dangerous to livestock and humans because they transmit serious diseases such as rabies and Chagas's disease. Vampire bats live in caves, tree hollows, and houses. They are mutual groomers, and an effective method of reducing their numbers is to coat a captured bat with a sticky poison and release it; when the bat returns to its roost the poison will be licked by other bats. Members of another bat family, the Megadermatidae, of the Old World tropics, are known as false vampire bats. They are exclusively carnivorous but do not feed on blood. The generic name Vampyrus belongs to a large, fruit-eating bat of Central and South America that was once mistakenly believed to suck blood. True vampire bats are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Chiroptera, family Desmodontidae.

vampire, in folklore, animated corpse that sucks the blood of humans. Belief in vampires has existed from the earliest times and has given rise to an amalgam of legends and superstitions. They were most commonly thought of as spirits or demons that left their graves at night to seek and enslave their victims; it was thought that the victims themselves became vampires. The vampire could be warded off with a variety of charms, amulets, and herbs and could finally be killed by driving a stake through its heart or by cremation. Sometimes the vampire assumed a nonhuman shape, such as that of a bat or wolf (see lycanthropy). Probably the most famous vampire in literature is Count Dracula in the novel Dracula by Bram Stoker.

Any of three species (family Desmodontidae) of tailless, brown, blood-eating bats native to the New World tropics. They grow to 2–3.5 in. (6–9 cm) long and weigh 0.5–2 oz (15–50 g). They run swiftly and leap with agility. They live in colonies in caves, hollow trees, and culverts, leaving after dark to forage low on the ground. They feed on quietly resting birds and mammals, including the occasional human, making a small cut with their sharp incisor teeth, often without disturbing the prey, and lapping the blood. The wounds are not serious but may transmit rabies or other diseases.

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In popular legend, a bloodsucking creature that rises from its burial place at night, sometimes in the form of a bat, to drink the blood of humans. By daybreak it must return to its grave or to a coffin filled with its native earth. Tales of vampires are part of the world's folklore, most notably in Hungary and the Balkan Peninsula. The disinterment in Serbia in 1725 and 1732 of several fluid-filled corpses that villagers claimed were behind a plague of vampirism led to widespread interest and imaginative treatment of vampirism throughout western Europe. Vampires are supposedly dead humans (originally suicides, heretics, or criminals) who maintain a kind of life by biting the necks of living humans and sucking their blood; their victims also become vampires after death. These “undead” creatures cast no shadow and are not reflected in mirrors. They can be warded off by crucifixes or wreaths of garlic and can be killed by exposure to the sun or by an oak stake driven through the heart. The most famous vampire is Count Dracula from Bram Stoker's novel Dracula (1897).

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