Hexanchus griseus is commonly caught in the fishery for deepwater spiny dogfish, and the liver of 'Madu miyaru' was prized for making oil to treat wooden dhonis.
The species can be found in both benthic and pelagic habitats, ranging from the continental and insular shelves to the upper slopes, with depths extending from the surface to a minimum of 1875 m. Juveniles are usually found in shallower waters, while adults inhabit deeper areas below 91 m. It feeds on a wide variety of marine life, including other sharks, rays, bony fishes and carrion. Reproduction is ovoviviparous, with litters ranging from 22 to 108.
distinctive characters
A large, heavy-bodied shark with six gill slits, small eyes, a broad head with a rounded snout, and a single dorsal fin has six rows of comb-like teeth on each side of its lower jaw, each with an inner edge that is serrated.