Marine biologists have discovered a new species of sea slug that lives in the deep, dark midnight zone of the ocean. It has a large gelatinous hood, a paddle-like tail, and bright bioluminescence. Bathydevius caudactylus It is so unique that it belongs to an entirely new family of crinoids. This animal is called the “mysterious mollusk”. Magazine December 2024 issue deep sea research.
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Discovering a mysterious mollusk
A team from Monterey Bay Aquarium Research Institute (MBARI) was the first to discover this mysterious mollusk over 20 years agowhile using a remotely controlled vehicle. Tiburon 8,576 feet offshore. they saw this strange creature 150 times or more Over the next 20 years.
Initially, they had trouble placing the mysterious mollusc into a known group. Bathydevius caudactylus It looks completely different than anything they’ve seen before. At one end it has a voluminous hooded structure, at the other end a flattened tail edged with several finger-like projections, and between them are many colorful internal organs. However, it has snail-like legs, which is why it got its nickname, the mysterious mollusk.
After collecting the specimen, they took it back to the lab for further examination. They investigated its anatomy and genetics and found that sea slug– Also known as sea slug.
Most sea slugs live along the ocean floor. They are also common in many coastal environments, such as coral reefs, kelp forests, and tidal pools, and a few nudibranch species are known to live in the ocean. deep sea ocean floor–Between 9,800 feet and 19,700 feet deep. Some are considered pelagic, living in the open ocean near the surface of the earth.
Bathydevius caudactylus It is the first nudibranch known to live in the deep water column. It lives in the midnight zone of the ocean, a large area of open water approximately 3,300 to 13,100 feet below the surface.
This hooded mollusk is now known to live off the Pacific coast of North America. MBARI scientists have discovered it as far north as Oregon and as far south as Southern California. NOAA researchers similar looking animals
Mariana Trench in the Western Pacific Oceansuggesting that it may have an even larger distribution.
Food, safety and company
According to the team, Bathydevius caudactylus has evolved several unique solutions for finding food, safety, and companionship for living in the midnight zone.
Most sea slugs use their ratty tongues to It eats prey stuck to the sea floor. Instead, Bathydevius caudactylus It works a little more like a Venus flytrap. They use their spongy hoods to catch crustaceans. Several other unrelated deep-sea species, such as some jellyfish, tunicates, and sea anemones, use this feeding strategy.
[Related: The process sea slugs use to regrow severed body parts is surprisingly common.]
Bathydevius caudactylus They are usually found in open waters far below the earth’s surface and well above the ocean floor. They move by bending their bodies up and down to swim, or by drifting motionless with the current. To avoid being eaten, they use their transparent bodies to essentially hide out of sight. They quickly close their palates for a quick escape, much like a pulsating jellyfish.
if they are threatened, Bathydevius caudactylus They glow with bioluminescence and can distract and thwart hungry predators. In one instance, the researchers witnessed it glow and detach a steady, glowing finger-like protrusion from its tail to distract potential predators.
“When we first photographed the lights in the ROV, everyone in the control room let out a loud ‘ooh!’ sound. At the same time. We were all mesmerized by what we saw.” said Stephen Haddock, author and MBARI senior research fellow. stated in a statement. “It is only recently that cameras have been able to capture bioluminescence in high resolution and in full color. We can study the luminous behavior of deep-sea animals on land.
Like other sea slugs, Bathydevius caudactylus They are hermaphrodites, meaning they have both male and female reproductive organs. They seem to go down to the sea floor to spawn. The researchers observed how some of the animals used their muscular legs to attach themselves to the muddy ocean floor to release their eggs.
Credit: MBARI.
Video credit: MBARI.
After examining specific gene sequences in detail, Bathydevius caudactylus The sea slug is unlike any other known sea slug and is unique enough to be a member of a new family, Bathydeviidae. meanwhile two shallow sea nudibranchs They also use hoods to capture prey, which appears to be a convergent evolution of similar feeding methods. Bathydevius caudactylus is only distantly related to these species, and genetic analysis shows that First to diverge from its own branch of the sea slug family tree.
“What’s interesting to me about this mysterious mollusk is that it demonstrates how much we’re learning as we spend more time in the deep ocean, especially below 2,000 meters.” [6,551 feet]” said Haddock. “The presence of relatively large, unique, and shiny animals in previously unknown families highlights the importance of using new technologies to catalog this vast environment. The more we learn about deep-sea communities, the better we will be at making decisions and managing our oceans.”
