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
Bounty Trough the South Island's coast. It covers an area of approximately . Much of The Bounty Trough lies at depths of , and it marks an indentation in the "coastline" of the largely submerged continent of Zealandia. A curious feature of the Bounty Trough is that it marks the continuation of several main river features in the South Island – the "Otago Fan Complex". This is a distinct series of channels existing in the base of the trough which is an extension of the Clutha and Waitaki River systems. Both these rivers, especially the Clutha, are noted for their fast flow.