The dark and chilly depths of the ocean’s so-called “midnight zone” thousands of feet below the surface are home to numerous species of bizarre-looking and fearsome fish. Many of these creatures have oversized jaws filled with massive teeth.
But a deceptively vulnerable-looking fish is not only right at home in the very deepest ocean environment on Earth — where few creatures can survive — it’s also one of the region’s top predators.
And now, for the first time, scientists have collected specimens of this unusual creature. Dubbed the Mariana snailfish, it swims in the Mariana Trench near Guam, at a depth of about 26,200 feet (8,000 meters). [Infographic: Tallest Mountain to Deepest Ocean Trench]
The snailfish’s small, pink and scaleless body hardly seems capable of surviving in such a punishing environment, but this fish is full of surprises, researchers reported in a new study. The animal appears to dominate in this ecosystem, going deeper than any other fish and exploiting the absence of competitors by gobbling up the plentiful invertebrate prey that inhabit the trench, the study authors wrote.
The fish’s scientific name, Pseudoliparis swirei, includes a nod to 19th-century sailor Herbert Swire, who served on the naval expedition that discovered the Mariana Trench in the late 1800s, according to the study.
The Mariana Trench occupies a part of the ocean that is so deep, dark and cold that its name — the “hadal zone” — was taken from “Hades,” the Greek underworld, according to the National Oceanic and Atmospheric Administration. This region consists mostly of marine trenches and extends from depths of about 19,685 to 36,089 feet (6,000 to 11,000 m).
In addition to being pitch-black and frigid, that region experiences pressure that’s unendurable for many forms of life. At the bottom of the funnel-shaped Mariana Trench, the pressure reaches 15,750 lbs. per square inch; for an unprotected human, that pressure would crush the lungs “to the size of ping-pong balls” and compress every single air pocket in the body “until you were a tightly packed, humanoid-shaped flesh chunk,” according to the book “And Then You’re Dead: What Really Happens If You Get Swallowed by a Whale, Are Shot from a Cannon or Go Barreling Over Niagara” (Penguin Books, 2017).
Snailfish, however, do just fine under this crushing pressure. There are more than 300 species in the snailfish family, many of which are known to inhabit a range of ocean depths, where they gather…