Sleeper rays

Sleeper rays
Nark capensis
Systematics
Class : Cartilaginous fish (Chondrichthyes) Subclass : Euselachii Subclass : Plate gill (Elasmobranchii) without rank: Stingray (batoidea) Order : Electric rays (Torpediniformes) Family : Sleeper rays
Scientific name
Narkidae
Fowler , 1934

The sleeper rays (Narkidae ( Gr .: "Narke" = paralysis)) are a group of electric rays (Torpediniformes) living in the western Pacific and Indian Oceans , which, depending on the author, have the rank of a family or subfamily, then named Narkinae.

features

Sleeper rays grow to be six to half a meter long. Your body disc is rounded in front with usually a dorsal fin on the caudal peduncle. The rostrum is narrow and rod-shaped. The eyes are small, the mouth strong, very short and only slightly protruding (protractile). The lips are reinforced with cartilage, there is a shallow groove around the mouth. On the sides of the head are the electrical organs that have developed from muscles.

Genera and species

There are five genera and nine species:

Nark dipterygia

• Genus Electrolux Compagno & Heemstra, 2007 .
  • Electrolux addisoni Compagno & Heemstra, 2007 .
• Genus Heteronarce
  • Heteronarce bentuviai (Baranes & Randall, 1989) .
  • Heteronarce garmani Regan, 1921 .
  • Heteronarce mollis (Lloyd, 1907) .
• Genus Narke
  • Nark capensis ( Gmelin , 1789) .
  • Narke dipterygia (Bloch & Schneider, 1801) .
  • Narke japonica ( Temminck & Schlegel , 1850) .
• Genus Temera
  • Temera hardwickii Gray , 1831 .
• genus Typhlonarke
  • Typhlon brand aysoni (Hamilton, 1902) .

literature

• Joseph S. Nelson : Fishes of the World , John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
• Kurt Fiedler: Textbook of Special Zoology, Volume II, Part 2: Fish , Gustav Fischer Verlag Jena, 1991, ISBN 3-334-00339-6 .
• Compagno, LJV & PR LAST (1999): Order Torpediniformes. Narkidae. Sleeper rays . In Carpenter, KE & VH Niem (eds): FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific . Rome, FAO, 3: 1443-1446. PDF
• de Carvalho, MR, Seret, B. & LJV Compagno (2002): A new species of electric ray of the genus Narcine Henle, 1834 from the southwestern Indian Ocean (Chondrichthyes: Torpediniformes: Narcinidae) . South African Journal of Marine Science, 24: 135-149.

Web links

Commons : Sleeper Rays (Narkidae)  - Collection of images, videos and audio files

• Sleeper rays on Fishbase.org (English)