Roughies

Marine: mostly deep-sea dwellers. Distribution: Atlantic, Indian, and Pacific Oceans. On head: extensive mucous cavities separated by spinous ridges and covered with membranous skin. Angle of preopercle with a distinct spine. A single normal spine in pelvic fin; soft rays 6. Dorsal fin with 3-8 spines. A median ridge of scutes in abdomen. Interspecific variation in type of scales. Body very deep to moderately deep. Some species are bioluminescent.