 The diamond stingray ( Dasyatis dipterura ) is a species of stingray in the family <unk> . It is found in the coastal waters of the eastern Pacific Ocean from southern California to northern Chile , and around the <unk> and Hawaiian Islands . This bottom @-@ dweller generally inhabits sandy or muddy flats near rocky reefs and kelp forests , to a depth of 30 m ( 98 ft ) , though off Hawaii it may range considerably deeper . As its common name suggests , this species has an angular , diamond @-@ shaped pectoral fin disc that is plain brown or gray above , with rows of tubercles along the midline and on the " shoulders " . The long , whip @-@ like tail has both dorsal and ventral fin folds , which distinguish this ray from the closely similar <unk> stingray ( D. <unk> ) . It typically grows to 1 m ( 3 @.@ 3 ft ) across . 
