Since the original holotype from Kauai, Hawaii had been lost, Garrick designated a 2.0 m (6.6 ft) long male from Palliser Bay, New Zealand as a new type specimen.

[1][6] The prickly shark has a flabby and cylindrical body, with the adults markedly bulkier than juveniles, and a short, moderately flattened head.

The skin has a dense, uniform covering of non-overlapping dermal denticles measuring up to 0.4 cm (0.16 in) across, which are never fused together as in the bramble shark.

The prickly shark is plain brown or gray, often with a purplish tint, and has black trailing margins on the fins.

In the western and central Pacific, it has been reported off Japan, Taiwan, Victoria and Queensland in Australia, and New Zealand, as well as around the islands of Palau, New Caledonia, Tonga, Hawaii, and possibly the Gilberts.

In the eastern Pacific, it is known to occur from Oregon to El Salvador (including the Gulf of California), around the Cocos and Galapagos Islands, and off Peru and Chile.

[9] It is tolerant of low dissolved oxygen levels, allowing it to inhabit oceanic basins inaccessible to other sharks.

The sharks were inactive during the day, resting in discrete refuge areas located near the sea floor in deep, offshore waters.

They became active at dusk, swimming towards the coast to the head of the canyon and rising into the water column; this upward movement is likely related to feeding on schooling fishes.

Individual sharks seldom strayed from the local area and had very small home ranges, no more than 2.2 km2 (0.85 sq mi).

This species feeds on a variety of benthic and pelagic bony fishes, including hake, flounders, rockfishes, lingcod, topsmelt, mackerel, and herring, and on cartilaginous fishes, including elephantfishes (Callorhinchus), spiny dogfish (Squalus acanthias), young bluntnose sixgill sharks (Hexanchus griseus), and ghost catshark (Apristurus) egg cases.

[15] Interactions with divers show that the prickly shark behaves inoffensively towards humans, either tolerating contact or fleeing when closely approached.

[16] The International Union for Conservation of Nature (IUCN) has assessed the prickly shark as Data Deficient, citing its patchy known distribution and the continuing expansion of deepwater fisheries.