 In 1837 , Johannes Peter Müller and Friedrich Gustav Jakob Henle placed the porcupine ray in a new genus , Gymnura . As the name Gymnura was already in use , referring to the butterfly rays , later that year Müller and Henle replaced it with Urogymnus . Both names are derived from the Ancient Greek oura ( " tail " ) and gymnos ( " naked " or " unarmed " ) , referring to the lack of a tail sting . Other common names for this species include black spotted ray , rough @-@ skinned ray , roughback stingaree , Solander 's ray , and thorny ray . There may be more than one species of porcupine ray , as is currently recognized . 
