Atlantic Stingray

Atlantic Stingray, Hypanus sabina

The Atlantic Stingray, Hypanus sabina, whose common Spanish name is raya látigo de espina, is a species in the Whiptail Stringray or Dasyatidae Family, known collectively as rayas látigo in Mexico. This fish has very recently been reclassified from Dasyatis sabina. Globally, there are thirty eight species in the genus Hypanus, five of which are found in Mexican waters, three in the Atlantic and two in the Pacific.

The Atlantic Stingrays have oval bodies. Their disc resembles a spade and is slightly wider than it is long with concave front margins and rounded corners. They are brown dorsally with lighter coloration towards the margins of their disc. They have a yellowish-brown snout tip and yellowish tail folds. They are off-white ventrally. Some fish have a dark stripe along their midline. Larger fish have gray flecks near their tail base and are completely dark toward their tip. They have flattened pectoral fins that are continuous and extend from their head to their tail base. Their head is slightly elevated and has an elongated triangular snout with small eyes and spiracles dorsally and a mouth and gills ventrally. Mature fish have a row of spines along their back and larger females have spines around their eyes and spiracles. They have a long tapered tail with a low dorsal keel and a low short ventral keel; their tail is slightly longer than disc length with an oval cross-section that is whip-like. Their tail has a venomous spine mid-length that can measure up to four inches long.

The Atlantic Stingrays are an unusual species being found in both fresh and saltwater environments. They are found in waters above 15oC (59oF) and below 30oC (86oF) and make seasonal migrations when water temperatures move out of this range. When inshore they are found in shallow water at depths up to 20 feet; offshore they can be found at depths up to 80 feet. They reside within sand or silt/sand seabeds normally half submerged looking for prey or predators. They are one of the smallest stingrays with a maximum total length of 61 cm (24 inches) and 4.9 kg (11 pounds) in weight. Females are larger than males with disc width up to 37 cm (15 inches) and females up to 33 cm (13 inches). They feed on benthic invertebrates including amphipods, bivalves, clams, crustaceans and nereid worms, which they locate via electroreception utilizing rows of sensory cells known as “Ampullae of Lorenzini” that locate the weak electric fields generated by prey, including buried prey. They are preyed upon by various sharks, including the Bull Shark and the Tiger Shark, and by Atlantic Goliath Groupers; in fresh water they are preyed upon by American Alligators. They are a dimorphic species with females being larger and having longer tail spines than males; females also have denticles around their eyes while males have claspers and larger teeth than females. Reproduction occurs via aplacental viviparity with internal fertilization. Males develop elongated teeth during mating season which they use to bite and hold on to females during copulation. Embryos are sustained by a yolk sac for the initial sixty days after which they are nourished by uterine milk secreted by their mother. After gestation periods of four to five months one to four miniature adults are born with disc widths of 10.0 cm (3.9 inches) to 13.0 cm (5.1 inches).

The Atlantic Stringrays are found in all Mexican waters of the Atlantic with the exception that they are absent from of along the east coast of the Yucatán.

The Atlantic Stringray can be distinguished from other stingrays found in Mexican waters of the Atlantic by its small stature and elongated snout.

The Atlantic Stingrays are very abundant but not of interest to humans other than on a limited basis in the aquarium trade. When encountered in the wild they are not aggressive but will use their venomous tail spines if startled or stepped on inflicting very painful wounds that are not life-threatening. There is currently on-going biomedical and neurobiological research evaluating the potential of their venom for human applications. From a conservation perspective they are considered of Least Concern with a wide distribution, common and with stable populations. Their primary threat being habitat destruction related to water quality declines due to pollution. They are caught in large numbers as a by-catch by gill netters targeting flounder and are normally released unharmed.

Atlantic Stingray, Hypanus sabina, male. Fish caught from coastal waters off  Apollo Beach, Tampa Bay, Florida, March 2016. Disc length: 33 cm (13 inches). Weight: 1.8 kg (4.0 pounds). Catch, photo, and identification courtesy of George Brinkman, Guelph, Ontario, Canada.

Atlantic Stingray, Hypanus sabina. Fish caught from coastal waters off Apollo Beach, Tampa Bay, Florida, March 2016, by spearfishing. Disc lengths up to 37 cm (15 inches). Catch, photo, and identification courtesy of George Brinkman, Guelph, Ontario, Canada. Note: the tails of three of the pictured fish were significantly shortened upon collection perhaps by commercial fishermen who had caught these fish previously. Fish caught for use as bait targeting the Atlantic Goliath Grouper.

 

Atlantic Stingray, Hypanus sabina. Fish caught from coastal waters within the Cooper River Estuary, Charleston, South Carolina, June 2011. Total Length: 70 cm (28 inches); Disc Width: 41 cm (16 inches); Disc Length: 33 cm (13 inches); Tail: 37 cm (15 inches). Catch, photo and identification courtesy of Josh Leisen (lifelistfishing.com), Gaylord, MI.