Author: (Brauer, 1904)
Notolychnus valdiviae (Brauer, 1904)
Status in World Register of Marine Species:
Accepted name: Notolychnus valdiviae (Brauer, 1904) (updated 2009-06-25)
Diagnosis: dorsal finrays 11 (10-12); anal finrays 13 (12-14); pectoral finrays 12-13. Gillrakers 2 + 1 + 7-8, total 10-11. AO 4 + 4 (3), total 8 (7). Single black-edged supra-caudal gland present in both sexes, slightly larger in adult males than in adult females. Size: to 25 mm (max.).
Habitat: high-oceanic mesopelagic. Canaries: day at 400-700 m (maximum abundance at 400-500 m); night at 25-200 m, 300-500 m and 600-700 m. Bermuda: day at 401-700 m (maximum abundance at 501-600m), night at 50-350 m (maximum abundance at 51-100 m). Size stratification with depth during the day only. Juveniles migratory; adults migratory, partially migratory or non-migratory. Food: copepods, conchoecid ostracods and euphausiids, with (?) selectivity against ostracods (Canaries); copepods, amphipods, crustacean larvae and chaetognaths (Indian Ocean). Reproduction: caudal glands develop in both sexes at 11 mm; sexually mature from 19 to 24 mm. Spawning peak in early summer.
Distribution: Atlantic: widespread pattern, between 56° N and 40 S. Elsewhere: eastern Indian Ocean (between 9° and 32° S) and Pacific (between 0° and 32° S (western sector) and between 32° N and 30° S (eastern sector), but with 20° S southern limit in the Peruvian Transitional Zone).
Eggs, larvae and young stages. Tåning, 1918: 151, fig. 47; 1931: pl. 121 | Pertseva-Ostroumova, 1964: 85-86, fig. 6.
Otoliths (sagitta). Kotthaus, 1972b: 28, pl. 2 (fig. 11).