Japanese sawshark
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| Japanese sawshark | ||||||||||||||||
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| Pristiophorus japonicus Günther, 1870 |
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 Range of Japanese sawshark (in blue)
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The Japanese sawshark, Pristiophorus japonicus, is a sawshark of the family Pristiophoridae, found in the northwest Pacific Ocean around Japan, Korea, and northern China between latitudes 48° N and 22° N, from the surface to 500 m. Its length is up to 1.35 m.
The Japanese sawshark has a long, narrow, and narrowly tapering rostrum (rostrum length is 26% to 29% of its total length), and the distance from the rostral tip to the barbels is about equal or slightly greater than the distance from the barbels to the mouth; the distance from the rostral barbels to the nostrils is about equal to the distance from the nostrils to the first gill slits. There are about 15 to 26 large rostral teeth on each side of the rostrum in front of the barbels, with 9 to 17+ behind them; the distance from the mouth to the nostrils is 1.1 to 1.2 times the internarial space. There are tooth rows of 34 to 58 in the upper jaw. The dorsal and pectoral fins are covered with denticles in large specimens. The lateral trunk denticles are largely unicuspidate. The first dorsal fin origin is behind the free rear tips of pectorals by an eye length or more. The caudal fin is almost straight, with slender upper and lower lobes. The pectoral fins are well developed but not ray-like.
It lives on continental shelves and upper slopes on or near the bottom, but is also found in coastal waters on sand or mud bottoms. It feeds on small bottom organisms using its barbels to poke the bottom with its snout. Reproduction is ovoviviparous, with 12 young in a litter.
[edit] Trivia
[edit] References
- "Pristiophorus japonicus". FishBase. Ed. Ranier Froese and Daniel Pauly. May 2006 version. N.p.: FishBase, 2006.
