Squalus acanthias | 水產百科網

Thespinydogfish(Squalusacanthias),alsoknownasthespurdogandpikeddogfish,isabottom-dwellingsharkofthefamilySqualidae.

The spiny dogfish (Squalus acanthias), also known as the spurdog and piked dogfish, is a bottom-dwelling shark of the family Squalidae. It is a small shark, typically growing to lengths of 1.0 - 1.5 meters, and is distinguished by its slender build, greyish-brown colour (countershaded with white ventrally), dorsal white spots, heterocercal tail, lack of anal fin and characteristically, its possession of a defensive spine anterior to each dorsal fin. The species name acanthias refers to these two spines. In spite of its small size, the spiny dogfish is among the slowest-growing, latest maturing and longest lived of shark species. Males mature at around 11 years of age while females mature at around 18 - 21 years of age. They are estimated to live to up to 100 years, with Pacific animals growing slower, larger and living longer than Atlantic animals. Aplacental viviparous, they also have among the longest known ...