A bumpy, pink fish with blue eyes and beard-like appendages has been filmed hovering over the muddy bottom of Monterey Canyon, at a depth of more than 10,700 feet (3,300 meters) off the coast of California.
This strange little snailfish, captured on camera by a group led by researchers at the Monterey Bay Aquarium Research Institute (MBARI), turned out to be one of three newly identified snailfish species living in the perpetual darkness and crushing pressures of the ocean’s depths.
Snailfishes are considered unusual even by deep-sea standards. Some have a suction cup of sorts on their stomach that allows them to cling to rocks or hitch rides on other animals. With over 400 known species, snailfishes live in ecosystems ranging from shallow tide pools to the deepest trenches on Earth.
“In addition to being an important part of the ecosystem, snailfishes give us the opportunity to study evolution into the deep ocean within one family,” team leader Mackenzie Gerringer, an associate professor of biology at State University of New York at Geneseo, told Live Science.
“By comparing shallow-living snailfishes to their deep-living relatives, we can better understand what adaptations are required for life in the deep sea,” Gerringer added.
Scientists discovered the new pink, “bumpy” snailfish species (Careproctus colliculi) in 2019 while using a remotely operated vehicle to explore Monterey Canyon.
Later that year, dives with the human-occupied submersible Alvin found two more new snailfish species at a depth of 13,100 feet (4,000 m): the jet-black “dark snailfish” (Careproctus yanceyi) and the “sleek snailfish” (Paraliparis em), a slender species without a suction disk.
“Distinguishing snailfishes from one another is a puzzle,” Gerringer said. “We’re looking carefully at multiple features, such as the number of vertebrae and fin rays, the positions of sensory pores, and the shape and size of a specialized suction disk that some species use to stick their bellies to rocks.”
The team collected measurements and looked at the different features, along with genetic information, to compare the new specimens with every other known snailfish and find matches. “With each new piece of evidence, it became clear that these three fishes were undescribed species, not previously known to science,” she said.
The team’s findings, published Aug. 27 in the journal Ichthyology and Herpetology, show not only that snailfish are thriving at these crushing depths but also that a larger, richer biodiversity of the environment remains to be uncovered.
“Accessing the deep oceans is in itself the biggest challenge of this research and requires collaboration between engineers, scientists and ship crews,” Gerringer said. “It takes many people to discover a new deep-sea species, all bringing their expertise together to accomplish a shared goal..
“The fact that two undescribed species of snailfishes were collected from the same place, on the same dive, at one of the better-studied parts of the deep sea in the world highlights how much we still have to learn about our planet,” she said.
