Spotted Stingaree, Urolophus gigas

The spotted stingaree (Urolophus gigas) is a shallow water ray from the coast of southern Australia. It is a rare species inhabiting the rocky reefs, seagrass beds and has also been found in estuaries. The range of the spotted stingaree is from Albany, Western Australia, Lakes Entrance, Victoria, Bass Strait and the northern Tasmanian coast. It is a bottom-dweller of the continental shelf and intertidal zones to depths of 160 feet.

The disc of the spotted stingaree is oval and slightly longer than it is wide, being more circular in juveniles. The snout is usually smooth and rounded with no protruding tip. It has tiny eyes with large comma-shaped air holes behind them. Between the nostrils sets a skirt-shaped layer of skin with finely fringed edges. Inside the mouth is nine to twelve nipple-shaped structures resting on the floor with small oval-shaped teeth. It has five pairs of short gill slits.

The tail is 76 to 80 percent as long as the disc and is thick and oval-shaped at the base. A large dorsal fin is followed by a serrated stinger on top of the tail and the tail fin is lance-like and short. The skin is smooth and dark brown to black above, becoming lighter out to the margins and the underbelly is a shade of white.  Adults have white spots and the tail fin is usually dark brown to black with white edges. The spotted stingaree can grow to 31 inches long.

This species of ray is nocturnal usually staying buried in the sand or hidden within the rocks or seagrass during the day. It feeds mainly on crustaceans such as shrimp.

The males reach sexual maturity at around 17 inches long and the females at around 18 inches. During gestation the embryos feed on the mother’s uterine milk. At birth as many as 13 pups can be produced.

It is not as aggressive to humans as other stingarees when disturbed. The population is scarcely affected by trawlers and fishermen because of the species’ habitat. Though it could potentially be affected by habitat destruction, it is still considered of least concern by the International Union for Conservation of Nature.

Image Caption: Spotted stingaree (Urolophus gigas). Credit: Jasper Montana / Museum Victoria/Wikipedia (CC BY-SA 3.0)