Reprinted from Wetwebmedia.com with permission (BobFenner@WetWebMedia.com)
Stingrays, family Dasyatidae: Marine, brackish, freshwater (the subfamily Potamotrygonidae, which I have as a family here). Atlantic, Pacific and Indian Oceans. Nine genera, 69 species. To distinguish from the Round Stingrays, no caudal fin, tail longer than body, body disc more than 1.3 times as wide as long.
Dasyatis americana (Hildebrand & Schroeder 1928), the Southern Stingray. Western Atlantic; New Jersey to Brazil. To over six feet in diameter. Below: A full and business end view of a specimen in Tobago in the Lower Antilles and one in the Bahamas.
Dasyatis kuhlii (Muller & Henle 1841), Kuhl's or the Blue-Spotted Stingray. Indo-West Pacific, including the Red Sea. To twenty eight inches in width. Reef associated. Feeds on crustaceans (shrimps and crabs mainly). Venomous. One off Heron Island, Australia, and a smaller individual in N. Sulawesi (Lembeh Strait).
Dasyatis pastinaca (Linnaeus 1758), the Common Stingray. Northeast Atlantic and Mediterranean. To about two feet in diameter. London Aquarium image.
Himantura jenkinsii (Annondale 1909), Jenkins Whipray. Indo-Pacific; South Africa to Northern Australia. To a meter in width. This female showing the characteristic ridge of denticle spines off Redang, Malaysia.
Eagle and Bat Rays, family Myliobatidae: Atlantic, Indian and Pacific. Heads elevated above body discs. Very long tails. Five genera, 43 species.
Manta birostris (Donndorff 1798), a/the Manta Ray. The paddle-like extensions on the head used for directing food into this filter feeders mouth. Third largest fish species at more than 6.7 meters in width, two tons in weight. Circumtropical.
Myliobatis californica Gill 1865, the Bat Eagle Ray. Eastern Pacific, Oregon to the Galapagos Islands. To more than five feet in diameter. This cool water species is occasionally offered for sale as an aquarium fish... it's not, unless you have a swimming-pool size system. This one in the Aquarium of the Pacific, Long Beach, California.
Round Stingrays, family Urolophidae: Western Atlantic, eastern Indian and Pacific. Four genera, 37 species. Body disc less than 1.3 times width. Have caudal fins on moderately long tails.
Taeniura lymna (Forsskal 1775), the Bluespotted Ribbontail Ray (3) (aka the Bluespotted Stingray in the pet-fish trade). Indo-West Pacific, including the Red Sea. To fourteen inches in width. A commonly offered species in the ornamental marine interest, but rarely lives... due to shipping trauma, being kept in too-small quarters, lack of oxygen, scratches and subsequent infections... An aquarium and Red Sea specimen shown.
Urobatis (Urolophus) halleri (Cooper 1863), the Haller's Round Stingray (3). Eastern Pacific, California to Panama. To more than two feet in diameter. Another cool water species occasionally caught and offered in the aquarium trade out of California... One in the Sea of Cortez off of Mulege, Baja, California, another at a wholesalers in Los Angeles.
Urobatis jamaicensis (Cuvier 1816), the Yellow Stingray. Western Atlantic; North Carolina to Venezuela. To thirty inches wide. Aquarium and Cozumel photos.
Electric/Torpedo Rays, family Torpedinidae: Two genera, fourteen species; all marine. Atlantic, Pacific and Indian Oceans. Distinguished by pancake-like appearance and substantial electric shock they can/do produce to deter predators, stun prey.
Narcine brasiliensis (Olfers 1831), Brazilian Electric Ray. To 54 cm. Tropical west Atlantic. Aquarium pic.
Torpedo sinuspersici Olfers 1831, Marbled Electric Ray. Western Indian Ocean; Red Sea, East Africa to India. To 130 cm. in length. Red Sea image.
Guitarfishes, family Rhinobatidae: Looking like intermediaries between the Sharks and more "ray-like" cartilaginous fishes.
Rhinobatos productus Ayres 1854, the Shovelnose Guitarfish. Eastern Pacific; Californias, US, Mexico. To about five feet total length, 18kg weight. A cool to coldwater Ray that is too often offered in the aquarium interest as a tropical.
Trygonorrhina fasciata Muller & Henle 1841, the Southern Fiddler. Eastern Indian Ocean; Australian endemic. To more than four feet in length, 6.7 kg. Aquarium image.
Zapteryx exasperata (Jordan & Gilbert 1880), the Banded Guitarfish. Eastern Pacific; California to Peru. Rocky reefs, rarely buried in sand. To three feet in length. Cabo San Lucas photo.
Thornback Rays, family Platyrhinidae;
Platyrhinoidis triseriata (Jordan & Gilbert 1880), the Thornback Guitarfish. Eastern Pacific, San Francisco to Mexico's Baja. To three feet in length. Aquarium images.
Skates, family Rajidae: Found in all Oceans. Eighteen genera, 224 species. Slender tails with rows of denticles on their surface, often these animals backs have a row as well. Eggs in horny cases with four long tips.
Raja eglantiera Bosc 1800, the Clearnose Skate. Western Atlantic; Massachusetts to the Gulf of Mexico. To two feet in diameter. This one in the shallows in the Bahamas.
And a neat demonstration... a skate egg with a "window" cut in it and a piece of acetate secured for easy viewing of the developing youngster within. Pic made at Monterey Bay Aquarium.
Re: Goiter: A common cause of nutritional deficiency syndrome is goiter in cartilaginous fishes... Here's an afflicted ray being properly offered food that is iodine/ate enriched.
Dahlstrom, Joni. 1987. Torpedo Ray. The sea's shocking surprise package. Skin Diver 6/87.
Debelius, Helmut. 1978. The Blue-Spotted Stingray. TFH 10/78.
Donovan, Paul. 1997. Electric Rays. TFH 11/97.
Edmonds, Les. 1989. Stingrays in the aquarium. TFH 6/89.
Hargrove, Mic. 1998. Tank busting Batoids. MFM 8/98.
Michael, Scott. 1996. Beware of Bluespots. A bluespotted beauty that should be left on the reef. AFM 1/96.
Zimmer, Carl. 1999. The mystery of the Mermaid's Purse. The egg case of the Hedgehog Skate provides more than a safe environment. Natural History. 7-8/99.