Deepwater Lanternfish

Dorsal spines (total): 0; Dorsal soft rays (total): 11 - 14; Analspines: 0; Analsoft rays: 12 - 14

High-oceanic and bathypelagic (Ref. 4066), mostly found below 675 m (Ref. 4479, 4775). Vertical migration not observed (Ref. 4479, 4775). Occurs at 800-1550 m during the day and 800-1000 m at night (Ref. 5951).

High-oceanic and bathypelagic (Ref. 4066), mostly found below 675 m (Ref. 4479, 4775). Vertical migration not observed (Ref. 4479, 4775).

Taaningichthys bathyphilus

This is a large myctophid, growing to about 80 mm (Davy, 1972). The largest specimen taken during the program was 68 mm. Taaningichthys bathyphilus does not conform well to any of the distribution patterns described by Backus et al. (1977). Most capture records are from tropical and subtropical waters (Davy, 1972; Nafpaktitis et al., 1977). This species is uncommon in the Ocean Acre area. The collections contain 64 specimens; 26 were caught during the paired seasonal cruises, of which 17 were in discrete-depth samples, 15 of these in noncrepuscular tows.

DEVELOPMENTAL STAGES.—Juveniles were 17–30 mm, subadults 31–68 mm, and adults 48–66 mm. Except for a 28 mm male, juveniles could not be sexed. Females may grow to a larger size than males; all 12 specimens larger than 58 mm were females. No other external sexual dimorphism is apparent. Adult females contain ova as large as 0.4 mm in diameter, but most eggs were about 0.2 mm.

REPRODUCTIVE CYCLE AND SEASONAL ABUNDANCE.—This species may be an uncommon breeding resident of the study area. There are too few specimens to determine the life span. Spawning seems to be confined to spring and summer, as small juveniles and adults were caught only at those seasons.

The catch in late spring consisted of 18–20 mm juveniles, which presumably were recently spawned (all were caught in oblique samples), subadults 31–35 mm and adults 52–66 mm. This indicates the presence of two or more age classes. It is virtually certain that the juveniles and adults were at least a year apart in age; the subadults may or may not represent an additional year class.

By late summer additional spawning had occurred. Four of the seven fish caught by the IKMT were 17–21 mm (the smallest two are from oblique samples); the remaining three were adults 53–56 mm SL. Intermediate sizes were sampled by the Engel trawl, which took fish 35–66 mm.

Seven fish were taken in winter: two juveniles 26–30 mm, and five subadults 41–68 mm. The two smaller fish were approaching one year of age and the larger fish at least two years of age.

VERTICAL DISTRIBUTION.—This species was found below 800 m day and night. Diurnal depth range for all seasons combined was 801–1550 m, with one fish in each season taken deeper than 1250 m. Depth of maximum abundance could not be determined from day samples. Depth range at night in winter was 801–900 m (possibly deeper) and in late summer 901–1000 m. No discrete-depth captures were made at night in late spring (Table 129).

Taaningichthys bathyphilus was considered to be a bathypelagic species by Nafpaktitis et al. (1977). The above catch data show that the species inhabits depths within the mesopelagial near Bermuda.

Taaningichthys bathyphilus is a species of lanternfish.

circumglobal between 43°N and 68°S in all oceans

High-oceanic and bathypelagic, mostly found below 675 m.

nektonic