Very elongate and fusiform; snout long and narrowly rounded; no spiracles; eyes round, with nictitating membrane; teeth serrated, long and triangular, broader and curved on top jaw, center tooth of top jaw very large; 5 short gill slits, last 2 over pectoral base; 1st dorsal fin low, its origin well behind pectoral fins; no ridge between dorsals; pectorals very long, narrow, slightly curved, pointed tips; tail base with small keel; tail asymmetric, well developed lower lobe, upper lobe notched under tip.
Back dark blue, flanks intense blue; belly white; tip of pectoral and anal dark.
Size: 380 cm.
Habitat: oceanic, epipelagic.
Depth: 0-350 m.
Southern California to the lower 2/3 of the Gulf of California and to Peru, and probably all the oceanic islands.