It was originally believed that the tubular eyes of this fish were fixed in place and, therefore, only provided a tunnel vision view of what was seen above its head.

[4] MBARI researchers Bruce Robison and Kim Reisenbichler observed that when prey such as small fish and jellyfish are spotted, the eyes rotate like binoculars, facing forward as it turns its body from a horizontal to a vertical position to feed.

[5] Macropinna microstoma was discovered in 1939 by marine biologist W. M. Chapman, in deep temperate waters off of the Pacific, Indian, and Atlantic oceans.

This protects its sensitive eyes from the nematocysts (stinging cells) of the siphonophores, from which it is believed to steal food.

Most of the time, the fish hangs motionless in the water, with its body in a horizontal position and its eyes looking upward.

M. microstoma is thought to be a pelagic spawner (the eggs are coated with a layer of oil that allows them to float on the closest surface of the sea until they hatch).

After hatching, the larvae begin to descend to the depths as they grow, feeding on zooplankton and other small particles of organic material.

It is broadly distributed across the northern Pacific Ocean, from the Bering Sea to Japan and Baja California.