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| regnum = Animalia | phylum = Chordata | classis = Chondrichthyes | subclassis = Elasmobranchii | superordo = Selachimorpha | ordo = Pristiophoriformes | ordo_authority = L. S. Berg, 1958 | familia = Pristiophoridae | familia_authority = Bleeker, 1859 | subdivision_ranks = Genera | subdivision = * ''Pliotrema'' Regan, 1906 * ''Pristiophorus'' J. P. Müller & Henle, 1837 }} The sawsharks or saw sharks are an order (Pristiophoriformes) of sharks bearing long, blade-like snouts edged with teeth, which they use to slash and disable their prey. Most occur in waters from South Africa to Australia and Japan, at depths of and below; in 1960, the Bahamas sawshark was discovered in the deeper waters (640 m to 915 m) of the northwestern Caribbean. ==Description and biology== Sawsharks have a pair of long barbels about halfway along the snout. They have two dorsal fins, but lack anal fins, and range up to in length.〔(FishBase )〕 Genus ''Pliotrema'' has six gill slits, and ''Pristiophorus'' the more usual five. The teeth of the saw typically alternate between large and small. These sharks typically feed on fish, squid, and crustaceans, depending on species. They cruise the bottom, using the barbels and ampullae of Lorenzini on the saw to detect prey in mud or sand, then hit victims with side-to-side swipes of the saw, crippling them. Although they are similar in appearances, sawsharks are distinct from sawfishes. Sawfishes have a much larger maximum size, lack barbels, have evenly sized rather than alternating sawteeth, and have gill slits on their undersurface rather than on the side of the head. 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「sawshark」の詳細全文を読む スポンサード リンク
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