Monterey Bay Aquarium Research Institute (MBARI) scientists said in a press release on Tuesday that while Bathydevius caudactylus is classified as a sea slug, it was nicknamed the "mystery mollusk" because the creature was unlike any other that’s been ...

One of the weirdest sea slugs known to science has been discovered at a staggering depth, swimming around right down in the Midnight Zone between 1,013 to 4,009 meters (3,323 to 13,153 feet). As well as becoming the first sea slug known to live in the deep-water column,

MBARI researchers have discovered a remarkable new species of sea slug that lives in the deep sea. Bathydevius caudactylus swims through the ocean's midnight zone with a large gelatinous hood and paddle-like tail,

It's named Bathydevius due to its "devious" nature that fooled the scientists at first, while caudactylus refers to the dactyls -- the fingerlike projections on its tail.

“Only recently have cameras become capable of filming bioluminescence in high-resolution and in full color,” Haddock added. “MBARI is one of the only places in the world where we have taken this new technology into the deep ocean, allowing us to study the luminous behavior of deep-sea animals in their natural habitat.”

More than two decades after spotting a mysterious, gelatinous, bioluminescent creature swimming in the deep sea, California researchers this week announced that it was a new species of sea slug.

A “remarkable” new sea slug nicknamed the “mystery mollusc” has been discovered swimming deep in the ocean’s “midnight” zone. The species has “unique” adaptations for life in the pitch black depths including a large gelatinous hood to trap prey,

It took nearly 25 years for biologists to discover that a swimming and glowing organism in the ocean’s midnight zone was actually a sea slug,” reported The New York Times.