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Salamanders are a group of amphibians typically characterized by a lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All present-day salamander families are grouped together under the scientific name Urodela. Salamander diversity is most abundant in the Northern Hemisphere and most species are found in the Holarctic ecozone, with some species present in the Neotropical zone. Salamanders never have more than four toes on their front legs and five on their rear legs, but some species have fewer digits and others lack hind limbs. Their permeable skin usually makes them reliant on habitats in or near water or other cool, damp places. Some salamander species are fully aquatic throughout their lives, some take to the water intermittently, and others are entirely terrestrial as adults. Unique among vertebrates, they are capable of regenerating lost limbs, as well as other damaged parts of their bodies. Members of the family Salamandridae are mostly known as newts and lack the costal grooves along the sides of their bodies typical of other groups. The skin of some species contains the powerful poison tetrodotoxin and these salamanders tend to be slow-moving and have bright warning coloration to advertise their toxicity. Salamanders typically lay eggs in water and have aquatic larvae, but great variation occurs in their lifecycles. In some species and some harsh environments, salamanders reproduce while still in the larval state. In literature and legend, the salamander is associated with fire, being supposedly unharmed by the flames, while clothes made from its skins or 'wool' were believed to be incombustible. More plausibly, salamanders were said to be intensely poisonous. Despite this, salamander brandy, a drink prepared by dunking live salamanders in fermenting fruit juices, is reputed to have hallucinogenic and aphrodisiac properties. The salamander's ability to regenerate lost body parts is being investigated and research is ongoing into any applications this may have for human medicine. ==Description== The skin lacks scales and is moist and smooth to the touch, except in newts of the Salamandridae, which may have velvety or warty skin, wet to the touch. The skin may be drab or brightly colored, exhibiting various patterns of stripes, bars, spots, blotches, or dots. Male newts become dramatically colored during the breeding season. Cave species dwelling in darkness lack pigmentation and have a translucent pink or pearlescent appearance.〔Cogger & Zweifel (1998), pp. 60–68.〕 Salamanders range in size from the minute salamanders, with a total length of , including the tail, to the Chinese giant salamander which reaches and weighs up to . Most, however, are between in length.〔Stebbins & Cohen (1995) p. 3〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「salamander」の詳細全文を読む スポンサード リンク
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