 A minority of authors place this species with the river stingrays in the family Potamotrygonidae.Preliminary morphological examination has suggested that the round ribbontail ray is more related to "Dasyatis" and Indo-Pacific "Himantura" than to the congeneric bluespotted ribbontail ray ("T. lymma"), which is closer to the amphi-American "Himantura" ("H. pacifica" and "H. schmardae") and the river stingrays.The round ribbontail ray has a thick pectoral fin disc wider than it is long, with a smoothly rounded outer margin.