Any of several genera of warm-water marine rays, constituting the family Mobulidae, that are wider than they are long. Extensions of the pectoral fins project from the front of the head, looking like devils' horns; these sweep plankton and small fishes into their mouths. The long, whiplike tail may have one or more stinging spines. Mantas swim near the surface by flapping their pectoral fins. The largest species, the powerful but inoffensive Atlantic manta, or giant devil, ray (Manta birostris), may grow to over 23 ft (7 m) wide; contrary to old tales, it does not envelop and eat divers.