Black dogfish to the clade formed by the granular dogfish ("C. granulatum") and combtooth dogfish ("C. nigrum"). The black dogfish is a common species, with a wide but discontinuous distribution in the temperate waters of the Atlantic Ocean; its range abuts, but does not extend into, the Arctic Ocean. In the northeast, it occurs from Iceland to Sierra Leone, including the Faroe Islands, southern Norway, and the Rockall Trough and Porcupine Seabight off Ireland. In the northwest, it is found from southern Greenland and Baffin Island to Virginia, being particularly abundant in the Laurentian Channel, and may occur further south to the
Rockall for Kilmarnock, said: "More people have landed on the moon than have landed on Rockall." Rockall is one of the few pinnacles of the surrounding Helen's Reef; it is located 301.3 km, or 162.7 nmi west of the island of Soay, St Kilda, Scotland, and northwest of Tory Island, County Donegal, Ireland. Its location was precisely determined by Nick Hancock during his 2014 expedition. The surrounding elevated seabed is called the Rockall Bank, lying directly south from an area known as the Rockall Plateau. It is separated from the Outer Hebrides by the Rockall Trough, itself located within the Rockall