Ragfish

The ragfish (Icosteus aenigmaticus) is a ray-finned fish of the northern Pacific Ocean; although classified as a bony fish, its skeleton is mostly cartilage, and the larvae have pelvic fins that disappear as they mature. It is the sole member of the family Icosteidae within the order Scombriformes.

The ragfish body is scaleless and limp, because of its cartilaginous skeleton and its flabby muscles. None of the fins have any spines. The dorsal and anal fins extend much of the length of the body, while the pelvic fins are absent. The coloration is generally a dark brown, and maximum known length is 2 m.