Disc strongly rhomboidal, much wider than long; wings strongly pointed; head wide, projecting from disc; pectoral fins extend along head and form two large soft horns; front margin of the pectoral fin ends above and before spiracle; eyes and spiracles on side of head; mouth ventral; small teeth on both jaws; length of tooth bands 54-65% of mouth width; teeth wider than long, smooth tips; ~ triangular filter plates in gills separate at tips; tail long, slender with small dorsal fin at base, a little shorter than disc width, with compressed base and without spine.
Upper surface black, purple or purplish grey; lower surface white, with outer half of pectorals blue-grey.
Size: 220 cm wide.
Habitat: schooling, pelagic in coastal and oceanic waters.
Depth: to 30 m.
Gulf of California to Peru; the Galapagos, Cocos and Malpelo.