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 fins to above the pelvic fins. These spots are more visible on immature spiny dogfish, and they fade as the shark matures. With some individuals, the spots completely disappear. The edges of the dorsal fins and the caudal fin have a dusky-colour at birth, but this colour quickly fades. The ventral surface of the dogfish ranges from pale grey to pure white.