A group of researchers have discovered a new species of fish during an expedition at the Mariana Trench, spot in the Pacific ocean known to be the deepest place on Earth.The previously unknown species has now set a new record as the world's deepest-dwelling fish.
Deep-sea biologist Alan Jamieson, from the Aberdeen University in the U.K, and colleagues spotted the deep sea snailfish during a month long voyage aboard the research vessel Falkor for the Hadal Ecosystem Studies (HADES), which aimed at surveying the deepest parts of the ocean. The survey involved deploying deep-sea sampling equipment more than 90 times into depths ranging between 5,000 and 10,600 meters.
The snailfish was filmed by the Hadal-Lander, U.K's deepest diving vehicle, 8,145 meters below the surface making it a record-holder for surpassing the depth reached by another snailfish species, the Pseudoliparis amblystomopsis, which previously held the record for deepest-living fish thriving at 7,703 meters down the waters.
Most animals have difficulty thriving in extreme depth because the intense pressure of the deep sea negatively affects the muscles and nerves as well as bends proteins out of shape but snailfish thrive at crushing depths and is often found from 6,500 to 7,500 meters below the surface.
Scientists, however, believe that there is a limit to how deep the fish can go because its body can no longer produce more of a substance known as osmolyte, which helps the cells withstand the pressures of the deep sea below 8,200 meters. The record-setting snailfish species is just right at the edge thriving at 8,145 meters.
"The deeper you go, the higher the concentration of this substance," said Jamieson said. "When you get to 8,200 meters, there's no way a theoretical fish can produce more. If a fish can go deeper, it's different from any other fish on the planet."
Jamieson said that previously unknown fish looks like a tissue paper that is being dragged through the water. He described its head as resembling the cartoonish dog's head and its body to be very delicate and translucent its liver can be seen through its side. The fish also appears to glide when it moves.
"This really deep fish did not look like anything we had seen before, nor does it look like anything we know of," Jamieson said. "It is unbelievably fragile, with large wing-like fins and a head resembling a cartoon dog".
Below are videos of the newly discovered deep-sea snailfish: