Electric ray (Tetronarce nobiliana)

Distribution data supplied by the Ocean Biodiversity Information System (OBIS). To interrogate UK data visit the NBN Atlas.Map Help

Summary

Description

The electric ray Tetronarce nobiliana is a large ray that may reach up to 1.8 m in length. It is usually dark greyish-blue to dark brown on the upper surface, sometimes with indistinct dark or white spots. The underside is white to cream in colour. It has a dorsoventrally flattened body with very small eyes and spiracles at the top of the head. Like all other electric rays, it has a very rounded snout and very rounded wings and pectoral discs. The body is thick and flabby, with soft, loose skin. The caudal fin is well developed. Tetronarce nobiliana has two dorsal fins on its tail that are situated close together.

Recorded distribution in Britain and Ireland

Recorded all around the coasts of Britain and Ireland.

Global distribution

Recorded along the east coast of North America and scattered around the north of South America. Records found along the north coast of France and Belgium and the south coast of Italy. Recorded along the north to the south-west coast of Africa as well as a few records off the coast of New Zealand and Taiwan.

Habitat

The electric ray is a demersal species usually found on sandy or muddy seabeds at depths between 10-150 m. It is often buried during the day but will swim in search of prey at night.

Depth range

10-150 m

Identifying features

  • Up to 1.8 m in length.
  • Very rounded disc-like body with a rounded snout.
  • Short tail with broad caudal fin.
  • Two dorsal fins positioned close together on the tail.
  • Uniform dark greyish-blue to dark brown colouration.
  • The inner edge of spiracles naked.

Additional information

Tetronarce nobiliana can be distinguished from the marbled electric ray Torpedo marmorata by its colouration, which is uniform dark greyish-blue to dark brown in the electric ray and marbled pale and dark brown in Torpedo marmorata.

Electric rays are best known for their highly specialized electrogenic organs. They are generally kidney-shaped organs, composed of stacks of striated muscle plaques. All these plaques are enervated on the same side, so that any muscular contraction generates electricity. This ultimately produces an external shock, used by the electric rays to incapacitate prey or deter potential predators (Stehmann & Bürkel, 1984).

Listed by

Bibliography

  1. Cadenat, J., Capapé, C. & Desoutter, M., 1978. Description d'un torpedinidae nouveau des cô tes occidentales d'Afrique: Torpedo bauchotae (Torpediniformes, Pisces). Cybium, 4, 29-42

  2. Campbell, A., 1994. Seashores and shallow seas of Britain and Europe. London: Hamlyn.

  3. Froese, R. & Pauly, D., 2004. Fishbase. A global information system on fishes. [On-line] http://www.fishbase.org, 2004-10-18

  4. Howson, C.M. & Picton, B.E., 1997. The species directory of the marine fauna and flora of the British Isles and surrounding seas. Belfast: Ulster Museum. [Ulster Museum publication, no. 276.]

  5. Shark Trust, 2009. An Illustrated Compendium of Sharks, Skates, Rays and Chimaera. Chapter 1: The British Isles. Part 1: Skates and Rays. [Cited 06-07-2018] Available from https://www.sharktrust.org/fact-files

  6. Stehmann, M. & Bürkel D.L., 1984. Torpedinidae. p. 159-162. In Fishes of the north-eastern Atlantic and Mediterranean (eds. P.J.P. Whitehead, M.-L. Bauchot, J.-C. Hureau, J. Nielsen and E. Tortonese). UNESCO, Paris.

  7. Whitehead, P.J.P., Bauchot, M.-L., Hureau, J.-C., Nielson, J. & Tortonese, E. 1986. Fishes of the North-eastern Atlantic and the Mediterranean. Vol. I, II & III. Paris: United Nations Educational, Scientific and Cultural Organisation (UNESCO).

Datasets

  1. NBN (National Biodiversity Network) Atlas. Available from: https://www.nbnatlas.org.

  2. OBIS (Ocean Biodiversity Information System),  2024. Global map of species distribution using gridded data. Available from: Ocean Biogeographic Information System. www.iobis.org. Accessed: 2024-10-30

Citation

This review can be cited as:

Barnes, M.K.S. 2008. Tetronarce nobiliana Electric ray. In Tyler-Walters H. and Hiscock K. Marine Life Information Network: Biology and Sensitivity Key Information Reviews, [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 30-10-2024]. Available from: https://marlin.ac.uk/species/detail/76

Last Updated: 24/06/2008