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Skate (fish)

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Skates
Temporal range: Late Cretaceous–Recent [1]
Barndoor skate, Dipturus laevis
Scientific classification
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Rajidae

Skates are cartilaginous fish belonging to the family Rajidae in the superorder Batoidea of rays. There are more than 200 described species in 27 genera.

Description and habitat

Skates have flat pectoral fins continuous with their head, producing a flat rhomboidal body shape. They also have two dorsal fins and a short, spineless tail. They have rough or thorny skin, and the males have additional thorns on the outer edge of their fins, with which to grasp the female during mating. There are five pairs of gill slits, located on the fish's underside. Skates are typically less than 1 metre (3.3 ft) in body length, although the largest species reach twice this size.[2]

Skates are carnivorous, feeding mostly on smaller fish and crustaceans. They are bottom-dwelling fish, living in most oceans, although they are absent from much of the Pacific. They range from shallow estuaries to deep sea environments, depending on species.[2]


Genera

Conservation

Skates have slow growth rates and, since they mature late, low reproductive rates. As a result skates are vulnerable to overfishing and it appears that skates have been overfished and are suffering reduced population levels in many parts of the world. The barndoor skate, Raja laevis, is currently listed with the IUCN as vulnerable due to being severely overfished.[3] However, population data is lacking to determine the exploitation of the big skate at this time.

See also

References

  1. ^ Froese, Rainer, and Daniel Pauly, eds. (2009). "Rajidae" in FishBase. January 2009 version.
  2. ^ a b Stevens, J. & Last, P.R. (1998). Paxton, J.R. & Eschmeyer, W.N. (ed.). Encyclopedia of Fishes. San Diego: Academic Press. p. 66. ISBN 0-12-547665-5.{{cite book}}: CS1 maint: multiple names: authors list (link)
  3. ^ http://www.flmnh.ufl.edu/fish/gallery/descript/bigskate/bigskate.html Florida Museum of Natural History