Scientists have formally identified a new species of snailfish, the deepest ever caught in the Mariana Trench. A related species has been filmed but never collected.
(From National Geographic/ By Craig Welch) — It’s cute, almost pink, and about twice as long as a cigar, with flesh so translucent you can see its liver from the outside. And it is the deepest fish ever caught.
Scientists today formally documented the world’s newest, deepest fish, Pseudoliparis swirei, an odd little snailfish caught at 7,966 meters in the Mariana Trench—nearly twice as far below the sea’s surface as Wyoming’s Grand Teton towers above it. The new species from the dark, frigid ocean region known as the hadal zone was first caught in 2014 and again early in 2017 but is only now being described.
Yet even though the deepest part of the ocean extends almost another 2 miles down to just shy of 11,000 meters, scientists suspect they are unlikely to ever find a fish that lives much deeper.
That’s because the pressure down deep is so enormous that fish may be chemically unable to withstand its destabilizing effects on proteins below about 8,200 meters.
While a host of animals can thrive down deep—foraminifera, odd decapod shrimp, sea cucumbers, microbes—no fish has ever been caught from the bottom quarter of the ocean. As of 2014, baited camera traps had been sent to the deepest regions 14 times across five Pacific Ocean trenches without ever even spotting a fish. The two most significant major deepwater trawling efforts—one byDanish researchers, the other in the 1950s by the Soviets—dropped nets 134 times to depths greater than 6,000 meters. No fish ever came up from a tow to the bottom 2,500 feet of water.
“There are real limitations to life in these trenches,” says Mackenzie Gerringer, a postdoctoral fellow at the University of Washington’s Friday Harbor Laboratories. Snailfish are thought to be able to handle pressures equal to the weight of 1,600 elephants. “They have evolved adaptations to that pressure to keep their enzymes functioning and membranes moving.”
Of course, scientists concede they could some day be proven wrong.
LIFE UNDER EXTREME PRESSURE
The new species, Pseudoliparis swirei, is named for an officer on the HMS Challenger, the 1870s British expedition that discovered thousands of new ocean species and led to the initial discovery of the trench. Challenger officer Herbert Swire, a navigational sub-lieutenant, published journals from the journey. “We named this fish after him in acknowledgment of the crews that serve on oceanographic research vessels,” Gerringer says. “It takes a lot of people to keep a ship running and we wanted to sincerely thank them.”
The species is almost certainly endemic to the trench, and appears to be…
Read the full article here: https://news.nationalgeographic.com/2017/11/deepest-sea-fish-identified-snailfish-pseudoliparis-swirei-spd/