The Thorntail stingray, Black stingray or Longtail stingray, Dasyatis thetidis, belongs to the stingray family Dasyatidae and is found in estuaries and lagoons and around reefs in the Indian Ocean, and around southern Australia, and New Zealand, at depths of up to 1443.57 ft (440 m). Its length is up to 13.12 ft (400 cm).
The Thorntail stingray is a large plain stingray with a broadly angular snout and pectoral disc, a thick-based and tapering tail ending in a slender whip, which is much longer than the body. It has no upper caudal finfold but long lower one ending far in front of the tail tip. The upper disc and tail of large juveniles and adults is roughened by large flat thorns, which are absent in small individuals. There are 1 or 2 stings on the tail which bear toxin glands.
Coloration is dark olive green, grey or black dorsally, and white ventrally without markings.
It is reported to enter freshwater in Australia. Generally found on soft bottoms and feeds on crabs, mantis shrimps, bivalves, polychaetes and conger eels.
The thorntail stingray is ovoviviparous.
Photo by Richard Ling