What is the longest bony fish?

  • Author(s)
    Mark McGrouther
  • Updated
    06/05/22
  • Read time
    2 minutes

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The Oarfish is reported to be the longest bony fish. It has a ribbon-like body that has been reliably documented to grow to 8m in length, however specimens up to 17m in length have been reported.

Oarfish found dead on the surface
An Oarfish found dead on the surface, about 5 km south-east of Pacific Light in the 1st shipping channel, Miami, USA, April 2006. Image: G. Musil
© G. Musil

Oarfish, Regalecus glesne, are a metallic silver in colour, with blotches and wavy markings on the body, and pink or red fins. They have a concave head profile, a highly protrusible mouth (a characteristic of the order Lampridiformes), a dorsal fin that runs the entire length of the body. It lacks an anal fin. Oarfish have tiny spines projecting laterally off each caudal and pelvic fin ray.

Oarfish, <i>Regalecus glesne</i>
A 4m long Oarfish washed ashore at Anna Marie Island, South of Tampa Bay, Florida, March 2002. It was initially assumed that the damage towards the tail of the fish resulted from an encounter with a boat propeller. This proved to be incorrect. Image: Duke Miller
© Duke Miller

Oarfish feed on invertebrates and fishes.

The species is found worldwide in all tropical and temperate marine waters. It is thought to live at depths between 20 m and 200 m.

People most often see Oarfish washed up on beaches. Encounters with live Oarfish are rare. They are sometimes seen on the surface, and this may contribute to tales of sea serpents.