The knifetooth dogfish is a rare species inhabiting continental slopes, usually mesopelagic although taken most often near the bottom. It is black in color, with small dorsal fin spines, and a short snout. There are small lanceolate teeth without cusplets in the upper jaw and huge high, knife-cusped cutting teeth in the lower jaw - its razor-edged lower teeth is used to attack and dismember large prey. The mouth is very wide and broadly arched, and the caudal fin has a weak subterminal notch and no lower lobe.
Its flesh is utilized dried salted for human consumption and for fishmeal.
Reproduction is ovoviviparous.