Ribbonfish
Ribbonfish, fish with long, slender bodies, found in all oceans. Ribbonfish inhabit the ocean depths and when found near the surface are usually dead. The dealfish grows to a length of about 8 feet (2.4 m). The oarfish grows to a length of more than 40 feet (12 m), but only a width of about 12 inches (30 cm) and a thickness of 3 inches (8 cm). In both species the dorsal fin extends the length of the back and forms a crest on the head. Ribbonfish may account for some of the stories of sea serpents.
Dealfishes belong to the genus Trachipterus of the family Trachipteridae. Oarfishes belong to the genus Regalecus of the family Regalecidae.