Cowtail stingray
(Pastinachus sephen)

The cowtail stingray (Pastinachus sephen) is a species of stingray in the family Dasyatidae, widespread in the Indo-Pacific region and occasionally entering freshwater habitats. Other common names include banana-tail ray, drab stingray, fantail ray, feathertail stingray, and frill tailed sting ray. This species is sometimes placed in the genus Dasyatis or Hypolophus (an obsolete synonym of Pastinachus).

The most distinctive characteristic of the cowtail stingray is the large, flag-like ventral fold on its tail, which is especially prominent when the ray is swimming. This species is targeted by commercial fisheries as a source of high-quality shagreen, a type of leather, and its populations are now under threat from heavy exploitation.

The cowtail stingray has a widespread distribution in the tropical waters of the Indo-Pacific, from South Africa and the Red Sea to Japan and Australia, including Melanesia and Micronesia. They are amphidromous and known to enter estuaries and rivers. This species is the most commonly reported stingray from fresh water in Southeast Asia, and there is a record from the Ganges River some 2,200 km (1,400 mi) from the sea. They are usually found on sandy bottoms in coastal waters and on coral reefs to a depth of 60 meters (200 feet).