Hemitriakis japanica (Müller & Henle 1839)

Ovoviviparous, embryos feed solely on yolk (Ref. 50449).

Occurs close inshore and offshore down to at least 100 m depth. Presumably feeds on small fishes, cephalopods and crustaceans.

Occurs close inshore and offshore down to at least 100 m depth. Presumably feeds on small fishes, cephalopods and crustaceans. Ovoviviparous, with 8 to 22 young in a litter. Size at birth about 20 to 21 cm. Utilized for human consumption.

fisheries: commercial

分布於西北太平洋區，包括臺灣、韓國、中國及日本。臺灣發現於北部及西部海域。

主要以流刺網、底拖網或延繩釣捕獲。肉質佳，生炒或煙燻即宜；魚鰭製成魚翅，品質佳。

體延長側扁。頭平扁。吻一般長，呈拋物線。眼裂縫狀，具瞬褶。前鼻瓣稍延長如葉片狀；不具口鼻溝。口裂呈圓弧狀；上唇溝往前延伸幾達上頜縫合部；齒刀狀，稍扁平，上下頜齒同形，兩行在使用，上下頜均具一尖直正中齒，正中齒及第1-2齒兩側各具2-3小齒頭，其餘齒具傾斜之齒尖及小齒尖。噴水孔小。盾鱗具3棘突3縱脊。背鰭2個，形狀相同，第二背鰭稍小；前緣圓凸，後緣深凹，上角鈍尖，下角延長尖突；第一背鰭起點在胸鰭後角稍後之上方；第二背鰭起點在臀鰭稍前；腹、臀鰭皆較第二背鰭小；胸鰭略大於第一背鰭；尾鰭狹長，稍大於頭長，上葉頗發達，下葉前部顯著三角形突出，中部較低，與後部間有一深缺刻，後部小三角形突出。體灰褐色，腹部、胸鰭和背鰭後緣為白色。

棲息於近海和外海至少100公尺深處。主要以小魚、頭足類及甲殼類為食。卵胎生，一胎可產下8-22幼魚，產下的仔魚可達20-21公分。

The Japanese topeshark (Hemitriakis japanica) is a species of houndshark, in the family Triakidae. It can reach a length of up to 1.1 m. It is found in the subtropical northwest Pacific from China, Taiwan, Korea, and Japan, between latitudes 40° N and 21° N.