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BOA - 4 reference results
boa, name for live-bearing constrictor snakes of the family Boidae, found mostly in the Americas. This family, which also comprises the egg-laying pythons of the Old World, includes the largest of all snakes, as well as many smaller ones. Members of the boa family have two functional lungs instead of one, as is found in other snakes, and vestiges of hind limbs; these primitive characteristics are indicative of their relationship to lizards. Each of the two tiny, internal leg bones ends in an external horny claw; the claws are much more prominent in males than in females. Boas capture their prey by striking with their teeth and simultaneously throwing their bodies in a coil around the victim. They then squeeze the animal so that, unable to expand its rib cage, it suffocates. Like other snakes, boas swallow the prey whole. Over 30 boa species are found from Mexico to South America, with the greatest variey in the tropics, and two in the United States. Boas may be terrestrial, arboreal, or burrowing. Some are brightly colored, like the green and white emerald tree boa of the tropics (Boa canina), or iridescent, like the wide-ranging rainbow boa (Epicrates cenchris). Best known is the boa constrictor (Constrictor constrictor), which lives in a variety of terrestrial habitats from S Mexico to central Argentina. It averages 6 to 9 ft (1.8-2.7 m) in length, occasionally reaching 14 ft (4.3 m), and has dark brown diamond markings on a lighter background. The South American anaconda (Eunectes murinus) is a semiaquatic boa that inhabits swamps and river shallows, catching animals that come to drink. The longest member of the boa family and the thickest of all snakes, it may reach 25 ft (7.9 m) in length and 3 ft (90 cm) in girth. The rubber boa (Charina bottae) is found in moist regions of the far W United States and extreme SW Canada. It is a burrower, about 18 in. (46 cm) long, with a narrow, blunt head, broad, blunt tail, and silver-green skin. It feeds chiefly on lizards and rodents. The rosy boa (Lichanura roseofusca) is found in chaparral in the SW United States and N Mexico; it grows about 3 ft (90 cm) long. It has large, dark brown spots on a lighter background. Several species of sand boa (Eryx) are distributed from India and central Asia to N Africa and SE Europe; all are burrowers in sand. There are also several boa species on Madagascar and several on Pacific islands. Boas are classified in the phylum Chordata, subphylum Vertebrata, class Reptilia, order Squamata, family Boidae.
Boa Vista, city (1996 pop. 154,166), capital of Roraima state, NW Brazil, on the Rio Branco. Its economy is based on the processing and shipment of minerals (gold, bauxite, diamonds, and gold) found in the surrounding region. Primary manufactures are alcohol and petroleum, construction goods, and metal products. Boa Vista became the capital of Roraima when it was created (as the federal territory of Rio Branco) in 1943.

Any of about 60 species of stout-bodied snakes (subfamily Boinae, family Boidae) found in both the Old and New Worlds, mostly in warm regions. Species vary in length from about 8 in. (20 cm) to more than 25 ft (7.5 m). Most are terrestrial or semiaquatic; some live in trees. Most species have blotches and diamonds on their brown, green, or yellowish body. Boas bite their prey, then kill by wrapping their body around the prey and crushing it. Several species have heat-sensitive lip pits for detecting warm-blooded prey, and most bear live young. Contrary to folklore, boas are not dangerous to humans.

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