Species: Etmopterus bigelowi, Blurred-smooth lanternshark

Etmopterus bigelowi Shirai & Tachikawa, 1993

Blurred-smooth lanternshark

Body slender; head and snout flattened, broad, at level of eyes head is wider than deep; snout long, thick, flat; no nictitating eyelids; spiracle large, behind eye; mouth short, at acute angle; upper teeth with a stout, thick central point plus 1 (female) to 3-5 (male) smaller points on each side, 19-24 rows, lower teeth compressed and blade-like, with small, oblique tips that become more erect in large fish, 25-39 rows; five gill slits, all before pectoral base, very short, length ~2X spiracle; two dorsal fins, second bigger than first, both with long thick grooved spines; first dorsal located just behind pectorals, distance from pectoral axil to 1st dorsal >1/3 interdorsal space, center of first dorsal nearer pectoral fin axil than origin of pelvics; 1st dorsal spine long & stout, >/ = 1st dorsal base; pectoral fin broad, ~triangular, ends just before 1st dorsal fin; no anal fin; no ridges between pectoral and pelvic fins, no precaudal pits, no keel on tail base; tail long; tail fin strongly asymmetrical, notch at top; denticles on sides of body without points, block-like, skin smooth.

Dark brown to blackish, a little darker below; a small white blotch between eyes; fins with light edges; inconspicuous, blurry dark areas on side of head, above pelvic fin, at lower origin of tail fin, on underside of pectoral; luminescent organs visible as black dots and streaks on underside of head and body.

Size: 73 cm.

Habitat: Outer continental shelf and upper slopes; partly epipelagic in open ocean.

Depth: 110-1000 m.

All three oceans: Gulf of Mexico to Argentina.