What is Spiny dogfish?
{{ Taxobox | name = Spiny dogfish | image = Spiny dogfish hokitika.jpg | status = VU | status_system = IUCN3.1 | regnum = [[Animal]]ia | classis = [[Chondrichthyes]] | ordo = [[Squaliformes]] | familia = [[Squalidae]] | genus = ''[[Squalus]]'' | binomial = ''Squalus acanthias'' | range_map = Squalus_acanthias_distmap.png | range_map_caption = Range of the spiny dogfish }} [[File:Squalus acanthias2.jpg|thumb|240px|The spiny dogfish]] The '''spiny dogfish''' (''Squalus acanthias'') is one of the most common and well known [[species]] of [[Squalidae|dogfish]]. It is a small [[species]] of [[shark]], with an average length of 28-39 inches (70–100&nbsp;cm), and reaching a maximum weight of 9.8&nbsp;kg. The dogfish is found in the [[Atlantic Ocean|Atlantic]] and [[Pacific Ocean]], and can be found from the surface to depths as deep as 1,460 metres. The spiny dogfish feeds mainly on [[pelagic zone|pelagic]] [[fish]] such as [[herring]], menhaden, capelin, sand lance, and [[mackerel]]. == Description== The spiny dogfish has a slim, long body and a flattened head. The snout is narrow, with a pointed tip. The eyes of this species are quite large. The first [[dorsal fin]] is located about halfway between the [[pectoral fin]]s and the [[pelvic fin]]s. The second dorsal fin is about two-thirds the size of the first one and is located behind the pelvic fins. On the front of each dorsal fin there is a sharp spine attached to them, giving the spiny dogfish its name. The first spine is about half as long as the second spine. The pectoral fins form nearly perfect [[equilateral triangle]]s, with rounded rear tips, and slightly concave rear margins. The pelvic fins are closer to the second dorsal fin than to the first dorsal fin. One the [[caudal fin]], there is no notch on the upper lobe and the lower lobe is not well-developed. There is no [[anal fin]] on the Spiny dogfish. The dorsal surface of the dogfish is slate-coloured and may have a brownish cast. There are rows of white spots along each side, from above the pectoral f