Dasyatidae

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Dasyatidae (stingrays; subclass Elasmobranchii, order Rajiformes) A family of rays of temperate to warm waters. Most species are marine but several are found in freshwater. Typically, they have one or two stout, serrated spines half-way down the back of the tail. Wounds inflicted by these spines can be very painful. Dorsal fins are usually absent; the head profile is continuous with that of the pectoral fins. Some species are found in trawl-nets at depths of more than 100 fathoms (183 m), others are estuarine carnivores (and unpopular with oyster farmers). One of the larger stingrays is Dasyatis brevicaudata (smooth stingray) of eastern Australia (3.5 m). The butterfly rays, which have a very short tail and a very wide body disc, are often included in this family. There are about 65 species, distributed world-wide.