First described and named in 1939, Macropinna microstoma was only recently seen in its natural habitat when a video emerged of the strange fish, languidly expecting its prey off California’s coast. A remotely-operated submersible from the Monterey Bay Aquarium and Research Institute caught images of the fish in 2004, which has a transparent head and queerly rotating eyes. It gives new meaning to thinking with a clear head.
The Macropinna microstoma is the only species of fish of the genus Macropinna, belonging to Opisthoproctidae, the barreleye family. Its nearest relatives include other finny creatures called ‘spookfish’, presumably because of their spectral aspect. They are found in tropical and semi-tropical waters of the Atlantic, Pacific and Indian oceans. They generally inhabit depths of 1200 to 7,000 feet in the oceanic zones known as mesopelagic and bathyalpelagic. Ranging in temperature from about 68 degrees Fahrenheit to 39 F, the depths in which the Macropinna microstoma lives are not only cold but quite dark.
Specimens hauled up from those depths in the past had been destroyed when reaching the surface. Thus, the unusual transparent head had not been evident until now.
Its unusually transparent, fluid-filled dome on its head, through which the lenses of its eyes can be seen, give it a bizarre visage. The eyes have a barrel shape and can be rotated to point either forward or straight up, looking through the fish's transparent dome as it expects its prey to drift down from above. Macropinna microstoma has a tiny mouth and most of its body is covered with large scales. It normally hangs around nearly motionless, while using its large pectoral fins for stability and with its eyes directed upward. In the low light conditions it is assumed the fish detects prey by its silhouette.
Researchers of the MBARI noted from images taken by a remotely-controlled submersible vehicle that when M. Microstoma spots its prey, such as small fish and jellyfish, that its eyes snap into a forward-looking position as it turns its body from the horizontal to a vertical position in order to strike. One researcher theorizes that it may steal food from siphonophores, that is to say colonial jellies, which resemble long gelatinous drifting ropes that inhabit the same murky depths.
Species: M. microstoma