Chaves' Lanternfish

Oceanodromous. Migrating within oceans typically between spawning and different feeding areas, as tunas do. Migrations should be cyclical and predictable and cover more than 100 km.

Dorsal spines (total): 0; Dorsal soft rays (total): 13 - 15; Analspines: 0; Analsoft rays: 12 - 14

Oceanic and mesopelagic, found at 600-800 m during the day, mainly at 40-175 m during the night, but locally nyctoepipelagic at the surface (Ref. 4479).

Lampadena chavesi

This moderately large lanternfish grows to 75 mm in the study area, almost its maximum known size of 80 mm (Hulley, 1981). Lampadena chavesi is a bipolar, questionably subtropical, species (Backus et al., 1977). It is uncommon in the study area, not being among the 20 most abundant lanternfish at any season. The collections contain 178 specimens; 52 were caught during the paired seasonal cruises, 31 of these in discrete-depth samples, of which 27 were caught in noncrepuscular tows (Table 23).

DEVELOPMENTAL STAGES.—Postlarvae were 6–17 mm, juveniles 17–37 mm, subadults 37–75 mm, and adult males 63–66 mm. No adult females were taken.

REPRODUCTIVE CYCLE AND SEASONAL ABUNDANCE.—Discrete-depth samples provide little information concerning the life history of L. chavesi. This may be due, in part, to net avoidance by larger specimens. For example, in late summer all specimens caught by the IKMT were 19–37 mm, and those caught by the Engel trawl were 20–75 mm, with more then 20 percent larger than 37 mm. Additionally, specimens taken with the IKMT have a unimodal size frequency distribution, and those taken with the Engel trawl show a bimodal distribution, with one group 20–43 mm, which presumbly represents the young of the year, and another group 63–75 mm, which were perhaps a year or more older than the smaller group. These data show that population estimates based on IKMT catches are low in late summer and, probably, at all seasons.

Abundance was greatest in late spring, when 18–27 mm juveniles comprised most of the population. In late summer abundance was much reduced, and in winter it was at a minimum (Table 78).

The presence of postlarvae in small numbers in winter and in late spring suggest a limited spawning season, perhaps in fall. Juveniles 18–27 mm were relatively abundant only in late spring. Four specimens, all from the winter cruises, were caught from October to April (6 negative cruises). These observations and the absence of adult females in the collections suggest that L. chavesi either does not breed in the study area, or that conditions for normal breeding and survival are marginal there.

VERTICAL DISTRIBUTION.—Day depth range for winter and late spring combined is 601–850 m. Vertical range at night for all three seasons combined is 50–150 m and 751–800 m (Table 78). The deepest night capture is a 17 mm juvenile, suggesting that recently transformed individuals do not migrate on a regular basis.

Atlantic Ocean: about 41°N to about north of 26°N, and between 26°S and 30°S in western sector

Found at depths of 600- 800 m during day, migrates to 40- 175 m at night.

nektonic

Known from seamounts and knolls