Smalleyed ray (Raja microocellata)
Facts
| Also known as: | painted ray and small-eyed ray |
|---|
| Kingdom | Animalia |
|---|---|
| Phylum | Chordata |
| Class | Chondrichthyes |
| Order | Rajiformes |
| Family | Rajidae |
| Genus | Raja (1) |
| Size |
Disc width: 80 cm (2) |
| Weight |
4.5 kg (2) |
Status
Classified as Lower Risk/ Near Threatened (LR/nt) on the IUCN Red List 2007 (1).
Description
Like other skates and rays, the most notable feature of the smalleyed ray is its large pectoral fins that provide gentle propulsion through the water (3). From above, the smalleyed ray appears rhomboid in shape (4), with greyish, olive or pale brown skin patterned with thin light streaks (2). Its snout is slightly pointed (4), and the underside, where the mouth is situated (3), is white (2). The long tail is slender (5), and contains muscles capable of emitting weak electrical discharges (6).
Range
Occurs along the Atlantic coast of northwest Europe, from Gibraltar to the British Isles, but is only abundant at a few sites, such as the Bristol Channel, UK, and Bertheaume Bay, France (1).
Habitat
Biology
Smalleyed rays are carnivorous fish that prey on small fish that dwell on the sea bottom (3) (8), using their interlocking teeth to grasp and crush the food (3). The weak electrical discharges that rays are capable of producing are thought to be used in interactions with other rays, as electrical activity is more frequent when they are in pairs or groups rather than solitary (6).
The smalleyed ray breeds in summer in the English Channel (2), producing eggs encased in a horny oblong case with four stiff, pointed tips (5) (8). A female lays between 54 and 61 eggs each year, depositing the precious capsules in sandy or muddy flats (8).
Threats
Smalleyed rays are both gamefish and a minor component of commercial fisheries (8), and their patchy distribution and localised abundance may make this species vulnerable to over-fishing. In addition, a preference for inshore and coastal habitat makes it more susceptible to habitat degradation and other human disturbances (1).
Conservation
At present, there are no known specific conservation measures in place for this species.
Authentication
This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk
Carnivorous: Flesh-eating.
Invertebrates: Animals without a backbone.
Pectoral fins: In fish, the pair of fins that are found one on each side of the body just behind the gills. They are generally used for balancing and braking.
References
- IUCN Red List (September, 2007)
http://www.iucnredlist.org - Miller, P.J. and Loates, M.J. (1997) Fishes of Britain and Europe. HarperCollins Publishers, London.
- Burnie, D. (2001) Animal. Dorling Kindersley, London.
- ReefQuest Centre for Shark Research (October, 2007)
http://elasmo-research.org/education/shark_profiles/rajiformes.htm - Nelson, J.S. (1994) Fishes of the World. Third edition. John Wiley and Sons Inc., New York.
- Evans, D.H. and Claiborne, J.B. (2006) The Physiology of Fishes. CRC Press, Boca Raton.
- Kaiser, M.J., Bergmann, M., Hinz, H., Galanidi, M., Shucksmith, R., Rees, E.I.S., Darbyshire, T. and Ramsay, K. (2004) Demersal fish and epifauna associated with sandbank habitats. Estuarine, Coastal and Shelf Science, 60: 445 - 456.
- FishBase (April, 2008)
http://www.fishbase.org/Summary/speciesSummary.php?ID=5492&genusname=Raja&speciesname=microocellata
