Black seadevils are small, deep-sea lophiiform fish comprising the family Melanocetidae. They are found in tropical to temperate waters of the Atlantic, Indian, and Pacific Oceans with one species known from the Ross Sea. Black seadevils are characterized by gelatinous, mostly scaleless, globelike body, a large head, and a generous complement of menacingly large, sharp. glassy fang-like teeth lining the jaws of a cavernous, oblique mouth. These teeth are depressible and present only in females.