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	{{otheruses1\|the family of marine fish}}
	{{Taxobox
	\| color = pink
	\| name = Stingrays
	\| image = Taeniura lymma 1.jpg
	\| image_width = 250px
	\| image_caption = ], ''Taeniura lymma''
	\| regnum = ]ia
	\| phylum = ]
	\| classis = ]
	\| subclassis = ]
	\| ordo = ]
	\| familia = '''Dasyatidae'''
	\| subdivision_ranks = Genera
	\| subdivision =
	'']''<br/>
	'']''<br/>
	'']''<br/>
	'']''<br/>
	'']''<br/>
	'']''<br/>
	See text for species.
	}}
	'''Dasyatidae''' is a family of ], ] ] ]es, related to ]s and ]s.

	Dasyatids are common in tropical coastal waters throughout the world, and there are ] species in ] ('']'' sp.), ], and ] ('']''). Most dasyatids are neither threatened nor ]. The species of the genera Potamotrygon, Paratrygon, and Plesiotrygon are all ] to the freshwaters of ].

	Dasyatids swim with a "flying" motion, propelled by motion of their large ] (commonly mistaken as "wings"). Their ] is a razor-sharp, barbed, or serrated cartilaginous spine which grows from the ray's whip-like tail (like a fingernail), and can grow as long as 37 cm (about 14.6 inches). On the underside of the spine are two grooves containing ]-secreting glandular tissue. The entire spine is covered with a thin layer of skin called the integumentary sheath, in which venom is concentrated.<ref>{{cite journal \| author = Meyer P \| title = Stingray injuries \| journal = Wilderness Environ Med \| volume = 8 \| issue = 1 \| pages = 24-8 \| year = 1997 \| id = PMID 11990133}}</ref> This gives them their common name of '''stingrays''' (a ] of "Stinger" and "Ray"), but the name can also be used to refer to any poisonous ray. Divers often refer to them as "Sea Devils".

	Some adult rays may be no larger than a human palm, while other species, like the ], may have a body of six feet in diameter, and an overall length, including their tail, of fourteen feet.

	Stingrays may also be called the '''whip-tailed rays''' though this usage is much less common.

	A group or collection of stingrays is commonly referred to as a "fever" of stingrays.

	==Feeding habits==
	] showing mouth]]
	Stingrays are flat so as to hide on the depths of the sea. They ruffle up the sand and hide beneath it. Since their eyes are on top of their body and their mouths on the bottom, stingrays cannot see their prey. Instead, they use the sense of smell and electro-receptors, similar to those of the ]. They feed primarily on ]s, ]s,and occasionally on small fish. Their mouths contain powerful, shell-crushing teeth. Rays settle on the bottom while feeding, sometimes leaving only their eyes and tail visible.

	==Stinging mechanism==
	].]]
	]
	].]]
	Dasyatids generally do not attack aggressively or even actively defend themselves. When threatened, their primary reaction is to swim away. However, when they are attacked by predators or stepped on, the barbed stinger in their ] is whipped up. Surfers or those who enter waters with large populations of stingrays have learned to slide their feet through the sand rather than stepping, as the rays are able to detect this and swim away. This attack is normally ineffective against their main ], ]s.<ref>{{cite web \| url = http://www.caribbeanmag.com/search/articles/Cayman_Islands/Stingray_city___diving___snorkeling_grand_cayman.html \| title = Stingray City - About Stingrays \| publisher = Caribbean Magazine}}</ref>

	Humans are usually stung in the ] region (depending on the size of the stingray); it is also possible, although less likely, to be stung by brushing against the stinger. Humans who harass stingrays have been known to be stung elsewhere, sometimes leading to fatalities. The stinger often breaks off in the wound, which is non-fatal to the stingray, and will be regrown. Contact with the stinger causes local ] (from the cut itself), pain and swelling from the venom, and possible later infection from bacteria on parts of the stinger left in the wound. Immediate injuries to humans include, but are not limited to: ], punctures, severed ] and possibly death. Fatal stings are extremely rare.
	The most famous stingray-related injury is the one that resulted in ]. On ], ], he was pierced in the chest with a stingray barb while snorkeling in Australia. Irwin's action of pulling the barb from his heart is most likely the leading contributor to his death. Cause of death was never conclusively determined, but speculation is heavy among the medical and scientific communites that he died from severe loss of blood from the heart to the abdominal cavity, and was dead by the time his team had brought him aboard Croc II.

	Treatment for stings includes application of near-scalding water, which helps ease pain by denaturing the complex venom protein, and ]s. Immediate injection of ] in and around the wound is very helpful, as is the use of adjunct opiates such as intramuscular pethidine. Local anesthetic brings almost instant relief for several hours. Other possible pain remedies include ] (] extract, contained in unseasoned powdered meat tenderizer), which may break down the protein of the toxins, although this may be more appropriate for ] and similar stings. One odd but usual method of pain relief is to urinate on the wound. The actual urine and sometimes vinegar are not benefitial themselves, but the warmth of the urine provides relief. Pain normally lasts up to 48 hours, but is most severe in the first 30–60 minutes and may be accompanied by ], ], ]s, ] and chills. All stingray injuries should be medically assessed; the wound needs to be thoroughly cleaned, and ] exploration is often required to remove any barb fragments remaining in the wound. Following cleaning, a ] is helpful to confirm removal of all the fragments.<ref>{{cite journal \| author = Flint D, Sugrue W \| title = Stingray injuries: a lesson in debridement \| journal = N Z Med J \| volume = 112 \| issue = 1086 \| pages = 137-8 \| year = 1999 \| id = PMID 10340692 }}</ref> However, not all remnants are radio-opaque; ] imaging is useful in difficult cases.

	== Reproduction ==
	Mating season occurs in the winter. When a male is courting a female, he will follow her closely, biting at her pectoral disc. During mating, the male will go on top of the female (his belly on her back) and put one of his two claspers into her vent.

	Most rays are ], bearing live young in "litters" of five to ten. The female holds the embryos in the womb without a placenta. Instead, the embryos absorb nutrients from a yolk sac, and after the sac is depleted the mother provides uterine milk.

	== As food ==
	]
	Rays are currently considered threatened in the wild. Their status is mostly due to pollution and development of their natural habitat, warm coastal waters. Rays are edible, and may also be caught as food by fishing lines or spears. Stingray recipes abound throughout the world, with dried forms of the wings being most common. For example, in ] and ], stingray is commonly ]d over charcoal, then served with spicy '']'' sauce. In ], eating pickled stingray ("kæst skata") on December 23 is an old tradition.<ref>{{cite web \|url=http://www.foodmuseum.com/ISyuletidelads.html \|title=Iceland's Christmas Foods \|accessdate=2006-12-23 \|work=[http://www.foodmuseum.com/ The FOOD Museum }}</ref> Generally, the most prized parts of the stingray are the wings, the "cheek" (the area surrounding the eyes) and the liver. The rest of the ray is considered too rubbery to have any culinary uses.
	While not independently valuable as a food source, the stingray's capacity to damage shell fishing grounds can lead to bounties being placed on their removal.

	<!-- -->== Viewing ==
	]
	] just yards away from tourists at Stingray City.]]
	]s.]]
	Stingrays are usually very docile creatures. The customary reaction of the stingray is to immediately flee the vicinity of a disturbance. Nevertheless, certain larger species are located in waters where they are easily excitable due to possible attacks from feeding sharks and should be approached with caution, as the stingray's defensive reflex and effort to flee may result in human contact with the stinger, resulting in serious injury or even (though rarely) death.

	Dasyatids are not normally visible to swimmers, but divers and snorkelers may find them in shallow sandy waters, more so when the water is unseasonably warm.

	In the ], there are several dive sites called ], where divers and snorkelers can swim with large ]s (''Dasyatis Americana'') and feed them by hand.

	There is also a "Stingray City" in the sea surrounding the ] island of ]. It consists of a large, shallow reserve where the rays live, and snorkelling is possible.

	In ] off the island of ] there is a popular marine sanctuary called ]. Here divers and snorkelers often gather to watch stingrays and ] that are drawn to the area by tour operators who feed the animals.

	Many Tahitian island resorts regularly offer guests the chance to "feed the stingrays and sharks". This consists of taking a boat to the outer lagoon reefs then standing in waist-high water while habituated stingrays swarm around, pressing right up against you seeking food from your hand or tossed into the water. The boat owners also "call in" sharks, which when they arrive from the ocean swoop through the shallow water above the reef and snatch food offered to them.

	]. Stingrays can be hard to see when they cover themselves with ].]]
	]

	== Species ==
	There are about seventy species in seven genera:
	]

	]

	]

	* Genus '']''
	** '']'' <small>(Nishida & Nakaya, 1988)</small>.
	** ], '']'' <small>(] & ], 1841)</small>.
	** ], '']'' <small>(Hildebrand & Schroeder, 1928)</small>.
	** ], '']'' <small>(Last, 1987)</small>.
	** ], '']'' <small>(] & ], 1841)</small>.
	** ] or ], '']'' <small>(Hutton, 1875)</small>.
	** ], '']'' <small>(], 1880)</small>.
	** ], '']'' <small>(Mitchill, 1815)</small>.
	** ], '']'' <small>(Smith, 1828)</small>.
	** ], '']'' <small>(] & Gilbert, 1880)</small>.
	** ], '']'' <small>(], 1908)</small>.
	** ], '']'' <small>(Stauch & Blanc, 1962)</small>.
	** ], '']'' <small>(Boeseman, 1948)</small>.
	** ], '']'' <small>(Lindberg, 1930)</small>.
	** ], '']'' <small>(] & ], 1801)</small>.
	** '']'' <small>(DeKay, 1842)</small>.
	** ], '']'' <small>(Nishida & Nakaya, 1988)</small>.
	** ], '']'' <small>(] & ], 1841)</small>.
	** ], '']'' <small>(Chu, 1960)</small>.
	** ], '']'' <small>(Roberts & Karnasuta, 1987)</small>.
	** ], '']'' <small>(], 1880)</small>.
	** ], '']'' <small>(Last, 1987)</small>.
	** ], '']'' <small>(], 1880)</small>.
	** ], '']'' <small>(], 1870)</small>.
	** ], '']'' <small>(Compagno & Roberts, 1984)</small>.
	** '']'' <small>(Gomes, Rosa & Gadig, 2000)</small>.
	** ], '']'' <small>(], 1892)</small>.
	** ], '']'' <small>(Miyosi, 1939)</small>.
	** ], '']'' <small>(Annandale, 1908)</small>.
	** ], '']'' <small>(Tokarev, 1959)</small>.
	** ], '']'' <small>(], 1892)</small>.
	** ], '']'' <small>(], 1758)</small>.
	** ], '']'' <small>(], 1870)</small>.
	** ], '']'' <small>(Lesueur, 1824)</small>.
	** ], '']'' <small>(Lesueur, 1817)</small>.
	** ], '']'' <small>(], 1892)</small>.
	** ], '']'' <small>(], 1899)</small>.
	** ], '']'' <small>(Capapé, 1975)</small>.
	** ], '']'' <small>(] & Hubbs, 1925)</small>.
	** ], '']'' <small>(] & ], 1841)</small>.

	* Genus '']''
	** ], '']'' <small>(Annandale, 1909)</small>.
	** ], '']'' <small>(Blyth, 1860)</small>.
	** ], '']'' <small>(Monkolprasit & Roberts, 1990)</small>.
	** ], '']'' <small>(Compagno & Heemstra, 1984)</small>.
	** ], '']'' <small>(] & Seale, 1906)</small>.
	** ], '']'' <small>(Hamilton, 1822)</small>.
	** ], '']'' <small>(], 1851)</small>.
	** ], '']'' <small>(Macleay, 1883)</small>.
	**'']'' <small>Last, Manjaji-Matsumoto & Kailola, 2006</small>.<ref>{{cite journal \| journal = Zootaxa \| url = http://www.mapress.com/zootaxa/2006f/z01239p034f.pdf \| volume = 1239 \| year = 2006 \| pages = 19-34 \| title = Himantura hortlei n. sp., a new species of whipray (Myliobatiformes: Dasyatidae) from Irian Jaya, Indonesia \| author = Last, Manjaji-Matsumoto & Kailola }}</ref>
	** ], '']'' <small>(] & ], 1801)</small>.
	** ], '']'' <small>(Annandale, 1909)</small>.
	** ], '']''
	** ], '']'' <small>(Chabanaud, 1923)</small>.
	** '']'' <small>Manjaji-Matsumoto & Last, 2006</small>.<ref>{{cite journal \| journal = Ichthyological Research \| volume = 53 \| issue = 3 \| year = 2006 \| pages = 291ff \| title = Himantura lobistoma, a new whipray (Rajiformes: Dasyatidae) from Borneo, with comments on the status of Dasyatis microphthalmus. \| author = Manjaji-Matsumoto & Last}}</ref>
	** ], '']'' <small>(Blyth, 1860)</small>.
	** ], '']'' <small>(Chen, 1948)</small>.
	** ], '']'' <small>(Sauvage, 1878)</small>.
	** ], '']'' <small>(Beebe & Tee-Van, 1941)</small>.
	** '']'' <small>(], 1852)</small>.
	** ], '']'' <small>(], 1852)</small>.
	** ], '']'' <small>(Werner, 1904)</small>.
	** ], '']'' <small>(Compagno & Roberts, 1982)</small>.
	** ], '']'' <small>(Whitley, 1939)</small>.
	** ], '']'' <small>(], 1852)</small>.
	** ], '']'' <small>(], 1775)</small>.
	** ], '']'' <small>(], 1852)</small>.
	** ], '']'' <small>(] & ], 1841)</small>.
	* Genus '']''
	** '']'' <small>Roberts, 2007</small><ref>{{cite journal \| journal = The Natural History Bulletin of the Siam Society \| volume = 54 \| year = 2006 \| pages = 285–293 \| title = Makararaja chindwinensis, a new genus and species of freshwater dasyatidid stingray from upper Myanmar. \| author = Roberts}}</ref>
	* Genus '']''
	** ], '']'' <small>(], 1775)</small>.
	**'']'' <small>(Last, Manjaji & Yearsley, 2005)</small>.<ref>{{cite journal \| journal = Zootaxa \| url = http://www.mapress.com/zootaxa/2005f/z01040p016f.pdf \| volume = 1040 \| year = 2005 \| pages = 1-16 \| title = Pastinachus solocirostris sp. nov., a new species of Stingray (Elasmobranchii: Myliobatiformes) from the Indo-Malay Archipelago \| author = Last, Manjaji & Yearsley }}</ref>
	* Genus '']''
	** ], '']'' <small>(], 1832)</small>.
	* Genus '']''
	** ], '']'' <small>(], 1817)</small>.
	** ], '']'' <small>(], 1775)</small>.
	** ], '']'' <small>(] & ], 1841)</small>.
	* Genus '']''
	** ], '']'' <small>(] & ], 1801)</small>.
	** ], '']'' <small>(Smith, 1863)</small>.

	==References==
	<!--<nowiki>
	See http://en.wikipedia.org/Wikipedia:Footnotes for an explanation of how to generate footnotes using the <ref> and </ref> tags, and the template below.
	</nowiki>-->
	{{reflist}}

	==Bibliography==
	* {{FishBase family \| family = Dasyatidae \| month = August \| year = 2005}}

	==External links==
	{{commonscat\|Dasyatidae}}
	* – Information on stingray poison.
	* and at ], ]

	]
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Revision as of 01:35, 8 February 2008