Body dark olive gray to almost black on the back, shading to bluish gray ventrally, scutes black. Upper profile of the head steep, the anterior part slightly concave, mouth relatively large. Tail deeply forked. Dorsal and anal fins long.
Size up to 1 m.
An oceanic and insular species, very much restricted to clear oceanic waters, down to 350 m. Not commonly found in shallow banks. Sometimes seen near the drop-off at the outer edge of reefs. Occasionally forming schools. Feed on fishes at night.
Uncommon to rare Florida, Bahamas and Caribbean.