Soft-nosed rays

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Soft-nosed rays
Bathyraja abyssicola, image from the Davidson Seamount from a depth of 2373 m.

Bathyraja abyssicola , image from the Davidson Seamount from a depth of 2373 m.

Systematics
Class : Cartilaginous fish (Chondrichthyes)
Subclass : Euselachii
Subclass : Plate gill (Elasmobranchii)
without rank: Stingray (batoidea)
Order : Rajiformes
Family : Soft-nosed rays
Scientific name
Arhynchobatidae
Fowler , 1934

The soft-nosed rays ( Arhynchobatidae) are a family of rays (Batoidea). It occurs in all oceans, from the Arctic Ocean to the Southern Ocean and from coastal regions to the deep sea, but is rare in tropical areas. Some species also go into brackish water .

features

Soft-nosed rays reach lengths of just over 20 cm ( Psammobatis extenta ) to 3.5 meters ( Bathyraja hesperafricana ) and have a more or less rhombic body. Its mouth is straight to curved and has numerous teeth. There are five paired gill slits on the underside of the head. The tail is slender and has lateral folds. Soft-nosed rays usually have two rather small dorsal fins, which are located far back just before the tail end, and a reduced caudal fin. Electrical organs are poorly developed; they developed from the tail muscles. In most species, the skin is partially covered with thorns. Often they are in rows along or parallel to the center line of the back.

Soft-nosed rays lay eggs (oviparous). The eggs are horny capsules with four long holding threads. Fossils suggest that the oviparity of the reverse family evolved from viviparous ancestors.

Genera and species

swell

literature

  • Joseph S. Nelson : Fishes of the world , Fourth Edition, Wiley & Sons, Hoboken 2006, ISBN 978-0-471-25031-9
  • Last, PR, Weigmann, S. & Yang, L. (2016): Changes to the nomenclature of the skates (Chondrichthyes: Rajiformes). Pages 11 to 34 in Last, PR & Yearsley, GK (Ed.) (2016): Rays of the World: Supplementary information. CSIRO Australian National Fish Collection.

Individual evidence

  1. Psammobatis extenta on Fishbase.org (English)
  2. Bathyraja hesperafricana on Fishbase.org (English)

Web links

Commons : Arhynchobatidae  - Collection of images, videos and audio files