How does the stoplight loosejaw see?

The stoplight loosejaw (Malacosteus niger) is a fish in the order Stomiiformes. Its eyes belong to the vision type Deep-sea bioluminescence specialist: rod-only or many rod opsins tuned to blue bioluminescence; loosejaw far-red; tubular or mirror eyes.

Measured in this species: colour and sharpness. Measured colour or sharpness: a measured receptor set or acuity in this species; other dials come from relatives or group defaults. Every value below carries its evidence level and sources; nothing is typed by hand.

Sample scene drawn in code: a face with red lips, a green shirt, red and green apples, flowers and a colour strip, as a person sees it. — The sample scene as a person sees it.

The same sample scene rendered by the See Like Animals engine for the stoplight loosejaw's eyes, using the values in the table below. — The same scene rendered for the stoplight loosejaw (60° field of view, daylight).

See your photo as the stoplight loosejawThis species is part of the full catalogue in the tool (full unlock). Your photo stays on your device.

What stands out

It has two colour receptor classes (a dichromat): reds and greens fall on one axis, as in red-green colour blindness in people.
Its sharpest vision resolves 5.6 cycles per degree: the finest stripe pattern it can tell apart from grey.

The six dials

Evidence levels: how the tiers work. "Measured" means a value measured in this species; "Estimated" values come from a close relative or an eye-size formula.

Vision values for the stoplight loosejaw (Malacosteus niger), catalogue-v1
Dial	Value	Evidence	Sources
Colour	Colour receptors 2 receptor classes: 425 nm (VS/SWS (violet)), 548 nm (LWS (long)) measured in this species	Measured (not re-verified)	^[1]
Sharpness	Acuity 5.6 cycles per degree median of 1 optical rows (method priority rule)	Measured	^[2]
Field of view	No value in the catalogue.
Sharp zones (foveas)	No value in the catalogue.
Night vision	Rods vs cones rod-dominated	Group default
Motion (flicker fusion)	No value in the catalogue.

Related animals

Half-naked hatchetfish same order (Stomiiformes)
Hatchetfish same order (Stomiiformes)
Atlantic silver hatchetfish same order (Stomiiformes)
Bighead portholefish same order (Stomiiformes)
Black-belly dragonfish same order (Stomiiformes)
Elongated bristlemouth same order (Stomiiformes)

More fish: all fish with measured vision data.

Sources

Murphy MJ, Westerman EL. 2022. Evolutionary history limits species' ability to match colour sensitivity to available habitat light. Proc R Soc B 289:20220612. Electronic supplementary Table S1. doi.org/10.1098/rspb.2022.0612
Caves EM, Sutton TT, Johnsen S (2017) Visual acuity in ray-finned fishes correlates with eye size and habitat. J Exp Biol 220:1586-1596. Table S1.. doi.org/10.1242/jeb.151183

Every value cites its sources (all sources). Data: catalogue-v1, built 2026-09-29. Accuracy notes: how accurate is this?