giant oarfish

The giant oarfish (Regalecus glesne) is a species of oarfish of the family Regalecidae. It is an oceanodromous species with a worldwide distribution, excluding polar regions. Other common names include Pacific oarfish, king of herrings, and ribbonfish.

R. glesne is the world's longest ray-finned fish. Its shape is ribbon-like, narrow laterally, with a dorsal fin along its entire length, stubby pectoral fins, and long, oar-shaped pelvic fins, from which its common name is derived. Its coloration is silver and blue with spots of dark pigmentation, and its fins are crimson. Its physical characteristics and undulating mode of swimming have led to speculation that it might be the source of many "sea serpent" sightings. In 2016, the TV show River Monsters concluded that the most likely origin of the sea serpent myth is the oarfish; host Jeremy Wade was filmed diving with two living, healthy giant oarfish in the Mediterranean Sea.