Skate
Juvenile thornback ray (Raja clavata )
The Real skates ( Rajidae ) are 17 genera and nearly 180 species, the largest family of rays.
Dissemination
Skates and rays live in all oceans from the Arctic to the Antarctic. Most species live in the temperate seas of mud, sand or gravel bottom. In the tropics, they are rare. In Polynesia, Hawaii, Micronesia, the Caribbean coast of South America and in coral reefs they are missing.
Appearance
The Real skates have a rhombic, strongly flattened body, the slim, stingless tail is clearly separated. On both sides of the tail they have weak electric organs. There are species with pointed and blunt rostrum. The skin is rough covered with small spines and tubercles. The females are significantly larger than the males. Shallow-water species are bright on the bottom, almost white. Species from the deep sea are dark on both sides. The animals move with undulating movements of their oversized pectoral fins.
The largest Skates and rays is the deep-water species Bathyraja hesperafricana who lives on the coast of West Africa at depths 750-2000 meters and is almost 3.5 meters long. One of the smallest species, with a maximum of 31.3 cm (females ) and 29.5 cm (males) of occurring near the coast in the South Atlantic off Brazil rays Psammobatis extenta.
The most famous Rajide is the thornback ray (Raja clavata ), who lives on the coasts of Europe from the Black Sea to the Barents Sea. It is also spread the stain skate ( Raja montagui ). The common skate (Dipturus batis) is now considered " critically endangered " on the IUCN Red List.
Reproduction
In contrast to all other rays, which are ovoviviparous ( egg - live - giving birth ), place the genuine rays eggs. The horny egg case is rectangular, with a thread on every corner. In the capsule are slots through which the sea water flow, and can provide the embryos with oxygen. One can recognize the type of the shape of the eggs. The young hatch after Rays 4-14 months.
Inside systematics
- Tribus Amblyrajini Genus Amblyraja Malm, 1877 Amblyraja badia ( Garman, 1899)
- Amblyraja doellojuradoi ( Pozzi, 1935)
- Amblyraja frerichsi Krefft, 1968
- Amblyraja georgiana (Norman, 1938)
- Arctic skate ( Amblyraja hyperborea ) ( Collett, 1879)
- Starry ray ( Amblyraja radiata) ( Donovan, 1808)
- Amblyraja reversa ( Lloyd, 1906)
- Amblyraja robertsi ( Hulley, 1970)
- Breviraja claramaculata McEachran & Matheson, 1985
- Breviraja marklei McEachran & Miyake, 1987
- Breviraja Mouldi McEachran & Matheson, 1995
- Breviraja nigriventralis McEachran & Matheson, 1985
- Dactylobatus armatus Bean & Weed, 1909
- Sand skate ( Leucoraja circularis ) ( Couch, 1838)
- Leucoraja compagnoi ( Stehmann, 1995)
- Leucoraja erinacea ( Mitchill, 1825)
- Shagreen ray ( Leucoraja fullonica ) (Linnaeus, 1758)
- Leucoraja garmani ( Whitley, 1939)
- Leucoraja leucosticta ( Stehmann, 1971)
- Maltese skate ( Leucoraja melitensis ) ( Clarck, 1926)
- Cuckoo ray ( Leucoraja naevus ) ( Müller & Henle, 1841)
- Leucoraja ocellata ( Mitchill, 1815)
- Leucoraja wallacei ( Hulley, 1970)
- Rajella annandalei ( Weber, 1913)
- Rajella barnardi (Norman, 1935)
- Deepwater skates ( Rajella bathyphila ) ( Holt & Byrne, 1908)
- Bigelow's skate ( Rajella bigelowi ) ( Stehmann, 1978)
- Rajella caudaspinosa ( From Bonde & Swart, 1923)
- Ghost - deep water stingrays ( Rajella dissimilis ) ( Hulley, 1970)
- Fyllarochen ( Rajella fyllae ) ( Lütken, 1887)
- Kukujevs skate ( Rajella kukujevi ) ( Dolganov, 1985)
- Rajella leopardus ( From Bonde & Swart, 1923)
- Rajella nigerrima ( de Buen, 1960)
- Rajella ravidula ( Hulley, 1970)
- Rajella sadowskii ( Krefft & Stehmann, 1974)
- Fenestraja maceachrani ( Seret, 1989)
- Fenestraja mamillidens ( Alcock, 1889)
- Fenestraja Plutonia ( Garman, 1881)
- Fenestraja sibogae ( Weber, 1913)
- Gurgesiella dorsalifera McEachran & Campagno, 1980
- Gurgesiella furvescens de Buen, 1959
- Kreffts skate ( Malacoraja kreffti ) ( Stehmann, 1977)
- Malacoraja presentation ( Garman, 1885)
- Samthautrochen ( Malacoraja spinacidermis ) ( Barnard, 1923)
- Neoraja africana ( Stehmann & Seret, 1983)
- Blue Dwarf skate ( Neoraja caerulea ) ( Stehmann, 1976)
- Neoraja carolinensis McEachran & Stehmann, 1984
- Neoraja stand manni ( Hulley, 1972)
- Cruriraja durbanensis ( From Bonde & Swart, 1923)
- Cruriraja parcomaculata ( From Bonde & Swart, 1923)
- Cruriraja triangularis Smith, 1964
- Common skate (Dipturus batis) (Linnaeus, 1758)
- Dipturus campbelli ( Wallace, 1967)
- Dipturus chilensis ( Guichenot, 1848)
- Dipturus crosnieri ( Seret, 1989)
- Dipturus diehli Soto & Mincarone, 2001
- Dipturus doutrei ( Cadenat, 1960)
- Dipturus ecuadoriensis ( Beebe & Tee - Van, 1941)
- Dipturus flavirostris ( Philippi, 1893)
- Dipturus gigas ( Ishiyama, 1958)
- Dipturus gudgeri ( Whitley, 1940)
- Dipturus innominatus ( Garrick & Paul, 1974)
- Dipturus johannisdavisi ( Alcock, 1899)
- Dipturus kwangtungensis ( Chu, 1960)
- Dipturus laevis ( Mitchill, 1818)
- Dipturus lanceorostratus ( Wallace, 1967)
- Dipturus leptocauda ( Krefft & Stehmann, 1975)
- White skate ( Dipturus linteus ) (Fries, 1838)
- Dipturus macrocauda ( Ishiyama, 1955)
- Dipturus mennii Gomes & Parago, 2001
- Dipturus nasutus ( Müller & Henle, 1841)
- Schwarzbäuchiger common skate (Dipturus nidarosiensis ) ( Storm, 1881)
- White skate ( Dipturus oxyrinchus ) (Linnaeus, 1758)
- Dipturus pullopunctatus (Smith, 1964)
- Dipturus springeri ( Wallace, 1967)
- Dipturus stenorhynchus ( Wallace, 1967)
- Dipturus tengu ( Jordan & Fowler, 1903)
- Dipturus Trachyderma ( Krefft & Stehmann, 1975)
- Okamejei acutispina ( Ishiyama, 1958)
- Okamejei australis ( Macleay, 1884)
- Okamejei boesemani ( Ishihara, 1987)
- Okamejei cerva ( Whitley, 1939)
- Okamejei heemstrai ( McEachran & Fechhelm, 1982)
- Okamejei Hollandi ( Jordan & Richardson, 1909)
- Okamejei kenojei ( Müller & Henle, 1841)
- Okamejei lemprieri ( Richardson, 1845)
- Okamejei meerdervoortii ( Bleeker, 1860)
- Okamejei pita ( Fricke & Al- Hussar, 1995)
- Okamejei powelli ( Alcock, 1898)
- Okamejei schmidti ( Ishiyama, 1958)
- Raja ackleyi Garman, 1881.
- African skate ( Raja africana) Capapé, 1977
- Mediterranean starry ray (Raja asterias ) Delaroche, 1809
- Raja binoculata Girard, 1855.
- Blonde ray (Raja brachyura ) Lafont, 1873 Blonde rays (Raja brachyura )
- Thornback ray (Raja clavata ) Linnaeus, 1758
- Raja cortezensis McEachran & Miyake, 1988.
- Raja eglanteria Bosc in Lacepede, in 1800.
- Raja equatorialis Jordan & Bollman, 1890.
- Raja herwigi Krefft, 1965.
- Raja inornata Jordan & Gilbert, 1881.
- Kleinäugiger skate ( Raja microocellata ) Montagu, 1818
- Mirror ray (Raja miraletus ) Linnaeus, 1758
- Spotted ray (Raja montagui ) Fowler, 1910
- Much Spotted ray (Raja polystigma ) Regan, 1923
- Raja pulchra Liu, 1932.
- Raurochen (Raja radula ) Delaroche, 1809
- Raja radiata Donovan 1807
- Raja Rhina Jordan & Gilbert, 1880 Raja Rhina
- Rondelet skate ( Raja rondeleti ) Bougris, 1959
- Raja senta Garman, 1885
- Raja spinicauda Jensen 1914
- Raja stellulata Jordan & Gilbert, 1880.
- Raja straeleni Poll, 1951.
- Raja texana Chandler, 1921.
- Marble Ray (Raja undulata ) Lacepede, 1802
- Raja velezi Chirichigno F., 1973.
- Saumrochen ( Rostroraja alba ) ( Lacepede, 1803)
The originally as a subfamily Arhynchobatinae the Skates and rays associated with " soft nose rays " are now mostly as a separate family (→ Arhynchobatidae ).