 The onefin electric ray was described by German naturalist Johann Friedrich Gmelin in 1789 , in the 13th edition of Systema Naturae . Gmelin 's name for the species was printed as Raja capensis in some copies of the book , and as Raja <unk> in others . The original spelling was probably <unk> , which modern taxonomists regard as a typesetting error as the etymology of capensis ( " of the Cape [ of Good Hope ] " ) is far more reasonable . Later sources have consistently used capensis , though to officially fix the specific epithet under that spelling would require a decision by the International Commission on Zoological Nomenclature ( ICZN ) . Gmelin did not refer to any type specimens . In 1826 , German naturalist Johann Jakob <unk> created the new genus Narke for this species , separating it from the other electric rays known at the time on the basis of its curved back and single dorsal fin . Later , more species were assigned to Narke . 
