Author: (Lütken, 1892)
Protomyctophum (Hierops) arcticum (Lütken, 1892)
Status in World Register of Marine Species:
Accepted name: Protomyctophum arcticum (Lütken, 1892) (updated 2009-06-25)
Diagnosis: dorsal finrays 12 (rarely 10, 11 or 13); anal finrays 22 (23, rarely 21 or 24); pectoral finrays 16 (15, rarely 14). Gillrakers 4 (rarely 3 or 5) + 1 + 14 (15), total 19 (20, rarely 18). AO 15 (16, rarely 14) with single black-rimmed luminous supra-caudal gland; females single coalesced infra-caudal luminous gland. Size: to 45 mm.
Habitat: high-oceanic, mesopelagic: day at 250-850 m (maximum abundance at 350 m); night 90-325 m (maximum abundance at 250 m). Food: no data. Reproduction: caudal glands develop in males at about 21 mm and in females at 25 mm; sexually mature from about 32 mm. Spawns both north and south of Secondary Polar Front(s) in eastern North Atlantic.
Distribution: endemic Atlantic: north temperate pattern (boreoarctic subpattern), south of about 70° to 47° N (eastern sector) and to about 40° N (western sector).
Eggs, larvae and young stages. Tåning, 1918: 151, fig. 48; 1931: pl. 111, fig. 2.
Otoliths (sagitta). No data.