Stoplight loosejaw (Malacosteus niger)

Scientific name: Malacosteus niger Ayres, 1848

The Stoplight loosejaw (Malacosteus niger) is a marine fish of the family Stomiidae. Native range: Worldwide in all oceans from Arctic latitudes at 66?N to approx. 30?S in the southern hemisphere; unknown in the Mediterranean.

Biology

Dorsal spines (total): 0; Dorsal soft rays (total): 17-21; Anal spines: 0; Anal soft rays: 18 - 24; Vertebrae: 47 - 51. This species possess the following characters: in male, postorbital photophore (PO) 5.8-11.9% upper jaw length (UJL), 1.5-3.1% SL; female PO 2.8-8.1% UJL, 0.8-11.9% SL; IP photophores 3-5 in 3-5 clusters.

Source: FishBase, licensed CC BY-NC 4.0.

Species facts

Scientific name: Malacosteus niger
Family: Stomiidae (Barbeled dragonfishes)
Order: Stomiiformes (Lightfishes and Dragonfishes)
Class: Actinopterygii (Ray-finned fishes)
Maximum length: 25.6
Depth range: 500–3886 m (1640–12749 ft)
Environment: Marine; bathypelagic; depth range 500 - 3886 m
Climate: Deep-water
Distribution: Worldwide in all oceans from Arctic latitudes at 66?N to approx. 30?S in the southern hemisphere; unknown in the Mediterranean.
Conservation status (IUCN): Not Evaluated
Threat to humans: Harmless
Uses: Fisheries: of no interest
Resilience: Medium, minimum population doubling time 1.4 - 4.4 years (Preliminary K or Fecundity.)

Sources

Taxonomy, distribution and biology data: FishBase (Froese, R. and D. Pauly, eds.), licensed CC BY-NC 4.0.

Last updated 27 September 2026