| Thorntail stingray | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
 |
||||||||||||||||
| Scientific classification | ||||||||||||||||
|
||||||||||||||||
| Binomial name | ||||||||||||||||
| Dasyatis thetidis Ogilby, 1899 |
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 440 m. Its length is up to 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.
References
- "Dasyatis thetidis". FishBase. Ed. Ranier Froese and Daniel Pauly. May 2006 version. N.p.: FishBase, 2006.
- Tony Ayling & Geoffrey Cox, Collins Guide to the Sea Fishes of New Zealand, (William Collins Publishers Ltd, Auckland, New Zealand 1982) ISBN 0-00-216987-8
