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Family Rajidae - Skates

Order:

Rajiformes

Class:

Elasmobranchii (sharks and rays)

No. of Genera:

No. of Species:

200

Environment:

Fresh: No Brackish: Yes Marine: Yes

Aquarium:

none

First Fossil Record:

upper Cretaceous, Ref.: Berg, L.S..1958

Remark:

Benthic rays occurring in all oceans, from Arctic to Antarctic waters and from shallow coastal shelfs to abyssal regions; rare in tropical shallow waters or near coral reefs; some species enter brackish waters. Disc quadrangular to rhomboidal. Mouth transversed to arched, with numerous teeth. Five pairs of ventral gill slits. Tail very slender, with lateral folds, usually 2 reduced dorsal fins and a reduced caudal fin. Electric organs weak, developed from caudal muscles. Skin prickly in most species, the prickles often in a row along midline of dorsal. Oviparous; eggs in a horny capsule with four long tips. A reversal to egg-laying from live-bearing was observed in this group based on fossil records (Ref. 50449). Skates feed on other benthic organisms. Skate wings are considered good eating. The following subgenus have been elevated to the genus level: Amblyraja, Dipturus, Fenestraja, Leucoraja, Okamejei, Rajella, Rostroraja (Ref. 27314).

Etymology:

Latin, raja = ray ( Ref. 45335).

Division:

Marine

Reproductive guild:

nonguarders

Typical activity level:

normal

Main Ref.:

Nelson, J.S..1994

Coordinator:

McEachran, John

Show species | Nominal species list for Rajidae | Identification keys | CAS specimen photos | References

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