A new species of sea slug that resides in the ocean's 'midnight zone' has been discovered with a glowing appearance.

In the ocean's midnight zone, a new species of glowing sea slug has been discovered by researchers.

On Tuesday, a press release from the Monterey Bay Aquarium Research Institute (MBARI) stated that Bathydevius caudactylus, although classified as a sea slug, was given the nickname "mystery mollusk" due to its unique characteristics that set it apart from any other species previously encountered.

Researchers were fooled by the "devious" nature of the mystery mollusk, whose genus name is Bathydevius, they said.

A sea slug known as Bathydevius is the first nudibranch to inhabit the deep sea. Its body consists of a large gelatinous hood and paddle-like tail. Additionally, it has the ability to emit bioluminescence.

The mysterious animal resides at depths of 1,000 to 4,000 meters or 3,300 to 13,100 feet below the ocean's surface in the midnight zone, posing a challenge for scientists who have spent decades cataloging it.

"Bruce Robison, MBARI Senior Scientist, stated that we have spent over 20 years studying the natural history of this intriguing species of nudibranch. Our findings contribute to a better understanding of the largest ecosystem on the planet."

Bathydevius evolved to survive uniquely in its environment, according to research findings.

The creature uses a hood to trap crustaceans like a Venus flytrap plant, and also hides from predators in plain sight by taking advantage of its transparent body.

The sea slug will light up with bioluminescence to deter and distract hungry predators. Researchers observed the creature illuminate and detach a "a steadily glowing finger-like projection from the tail, likely serving as a decoy to distract a potential predator."

Bathydevius, like other nudibranchs, is a hermaphrodite, possessing both male and female sex organs. According to researchers, the creature will descend to the seafloor to spawn, utilizing its muscular foot to secure itself to the muddy seafloor before releasing its eggs.

Thanks to the advanced underwater technology of the MBARI facility, scientists were able to compile the most comprehensive description of any deep-sea creature to date.

"According to MBARI Senior Scientist Steven Haddock, what excites him about the mystery mollusk is that it demonstrates how much we are learning as we spend more time in the deep sea, particularly below 2,000 meters. The fact that this relatively large, unique, and glowing animal belongs to a previously unknown family highlights the significance of using new technology to catalog this vast environment."