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The darters or snakebirds are mainly tropical waterbirds in the family Anhingidae having a single genus ''Anhinga''. There are four living species, three of which are very common and widespread while the fourth is rarer and classified as near-threatened by the IUCN. The term "snakebird" is usually used without any additions to signify whichever of the completely allopatric species occurs in any one region. It refers to their long thin neck, which has a snake-like appearance when they swim with their bodies submerged, or when mated pairs twist it during their bonding displays. "Darter" is used with a geographical term when referring to particular species. It alludes to their manner of procuring food, as they impale fishes with their thin, pointed beak. The American darter (''A. anhinga'') is more commonly known as the anhinga. It is sometimes called "water turkey" in the southern United States for little clearly apparent reason; though the anhinga is quite unrelated to the wild turkey, they are both large, blackish birds with long tails that are sometimes hunted for food.〔Answers.com (), BLI (2009), Myers et al. ()〕 ''Anhinga'' is derived from the Tupi ''ajíŋa'' (also transcribed ''áyinga'' or ''ayingá''), which in local mythology refers to a malevolent demonic forest spirit; it is often translated as "devil bird". The name changed to ''anhingá'' or ''anhangá'' as it was transferred to the Tupi–Portuguese Língua Geral. However, in its first documented use as an English term in 1818, it referred to an Old World darter. Ever since, it has also been used for the modern genus ''Anhinga'' as a whole.〔Jobling (1991), MW ()〕 ==Description== Anhingidae are large birds with sexually dimorphic plumage. They measure about in length, with a wingspan around , and weigh some . The males have black and dark-brown plumage, a short erectile crest on the nape and a larger bill than the female. The females have much paler plumage, especially on the neck and underparts, and are a bit larger overall. Both have grey stippling on long scapulars and upper wing coverts. The sharply pointed bill has serrated edges, a desmognathous palate and no external nostrils. The darters have completely webbed feet, and their legs are short and set far back on the body.〔Brodkorb & Mourer-Chauviré (1982), Myers et al. ()〕 There is no eclipse plumage, but the bare parts vary in color around the year. During breeding, however, their small gular sac changes from pink or yellow to black, and the bare facial skin, otherwise yellow or yellow-green, turns turquoise. The iris changes in color between yellow, red or brown seasonally. The young hatch naked, but soon grow white or tan down.〔Myers et al. ()〕 Darter vocalizations include a clicking or rattling when flying or perching. In the nesting colonies, adults communicate with croaks, grunts or rattles. During breeding, adults sometimes give a ''caw'' or sighing or hissing calls. Nestlings communicate with squealing or squawking calls.〔 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「darter」の詳細全文を読む スポンサード リンク
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