During its ongoing exploration of the Marianas Trench in the Pacific Ocean -- the world's deepest undersea formation -- scientists with the National Oceanic and Atmospheric Administration (NOAA) caught something special on video: a fish no one had ever seen alive before.
The NOAA team shot footage of a pale, nearly translucent representative of the family Aphyonidae, an eel-like clan that lives in the deepest of waters, from 8,000 to about 20,000 feet (2,438 to 6,096 meters) below the surface. It reminded viewers of "Casper," the ghostly octopus spotted by NOAA on a prior mission.
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NOAA researchers on the video (see below) brim with excitement at the sight of the small fish (typically running just under 4 inches -- 10 centimeters -- long), whose skin has no scales and no pigment.
It was spotted about 8,200 feet down (2,500 meters).
"I am sure this is the first time a fish in this family has ever been seen alive," NOAA fishery biologist Bruce Mandy said on the accompanying video below. "This is really an unusual sighting."
"Look at those eyes!" NOAA researcher and expedition team leader Shirley Pomponi exclaimed.
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In addition to the sighting itself being a thrill, the video may help answer an ongoing debate about the Aphyonidae. Mandy explains that some believe the fish live in the pelagic (not close to the bottom or the shore) zone while others think the aphyonidae are bottom dwellers.
While not conclusive, Mandy indicated, the video could present a "strong argument that, yes, this family is a bottom-living family."