; subclass Actinopterygii, order Salmoniformes)
A family of small (about 7 cm long) deep-sea fish that have an elongate body, a large mouth, and a single dorsal and a long anal fin. The pectoral and pelvic fins are small. A series of photophores is often present along the ventral side of the fish. Many species seem to be present in large numbers in the deep sea. There are about 60 species.
Subjects: Zoology and Animal Sciences.