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 fishing rights. Lord Kennet said of Rockall in 1971, "There can be no place more desolate, despairing and awful." It gives its name to one of the sea areas named in the shipping forecast provided by the British Meteorological Office. Rockall has been a point of interest for adventurers and amateur radio operators, who have variously landed on or briefly occupied the islet. Fewer than 20 individuals have ever been confirmed to have landed on Rockall, and the longest continuous stay by an individual was 45 days in 2014. In a House of Commons debate in 1971, William Ross, MP