MARINE HATCHETFISH

Sternoptychidae

Marine Hatchetfishes or Deep-Sea Hatchetfishes are a family of ray-finned fish. The name ‘Hatchetfish’ is derived from its laterally thin body that resembles a hatchet. Their skin is very metallic and has a rusty or silver tint. The hatchetfish’s eyes are extremely large and bulge outward from the head. This allows them to hunt in the dark waters. Lined along their belly they have photophores. To avoid being seen, the photophores mimic the light coming from above. They can match the color and intensity with extreme accuracy, leaving nothing but a thin outline. Only the largest of eyes can distinguish the two.

The Hatchetfish lives in the bathypelagic zone of tropical regions. They are nocturnal hunters, rising into shallower waters near dusk to feed on copepods and ostracods. Their large eyes allow them to spot the silhouettes of prey swimming above them.