词条 | saw shark |
释义 | saw shark any of about four species of long-snouted marine sharks of the family Pristiophoridae. Saw sharks are found off South Africa, Australia, and eastern Asia and are characterized by a long, slender, sawlike snout equipped with sharp, toothlike projections on each edge. They resemble the rays known as sawfishes but have a pair of barbels on the underside of the saw and have gill slits on the sides of the head, not underneath. Saw sharks grow to a maximum of about 1 m (3 feet) long. They feed on fish, striking and cutting their prey with their saws, but are harmless to humans. There are two genera of saw sharks: Pliotrema, with six pairs of gill openings, and Pristiophorus, with five. |
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