; subclass Actino-pterygii, order Perciformes)
A monospecific family (Icosteus aenigmaticus) of large (more than 2 m) marine fish that have a blunt snout, small eyes, and a distinct hump in front of the dorsal fin. The dorsal and anal fins are long, the pectoral fins are absent in adults. There is a considerable difference between the juvenile and adult stages, juveniles possessing a very deep body. Icosteidae occur in the N. Pacific.
Subjects: Zoology and Animal Sciences.