Scientists discover mysterious deep sea creature. It hunts with a hood.

It dwells in the midnight zone.

Scientists at the Monterey Bay Aquarium Research Institute identified an intriguing new deep sea species off of California. It's see-through, can glow, and nabs prey with a large hood. At one point while filming, researchers watched it detach one of its finger-like appendages, likely as a decoy for a predator. The glowing appendage floated away.

"When we first filmed it glowing with the ROV, everyone in the control room let out a loud 'Oooooh!' at the same time. We were all enchanted by the sight," Steven Haddock, a senior scientist at the institute, said in a statement.

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Below, you can view brilliant footage of the animal, which biologists have dubbed the "mystery mollusc." It now also has a scientific name, Bathydevius caudactylus, and after years of observation and genetic testing, scientists have concluded it's a species of nudibranch, more popularly known as sea slugs.

But this creature might not resemble, nor behave, like a typical bottom-dwelling slug.

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It primarily lives between some 3,300 to 13,100 feet below the ocean surface, a vast region of the lightless sea called the midnight zone (this zone accounts for some 70 percent of seawater on Earth but is largely unexplored). To eat, it uses a hood to "trap crustaceans like a Venus fly trap plant," the institute explains. It's a hermaphrodite (like other sea slugs), and exploits its transparency to hide in plain sight. But as described above, when needed it can detach parts of its body as a decoy.

Behold the "mystery mollusc":

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Bathydevius caudactylus is so unusual that it took 150 deep water sightings over 20 years before marine biologists could accurately identify the animal. The discovery has been published in the science journal Deep-Sea Research Part I.

"What is exciting to me about the mystery mollusc is that it exemplifies how much we are learning as we spend more time in the deep sea, particularly below 2,000 meters," Haddock said. "For there to be a relatively large, unique, and glowing animal that is in a previously unknown family really underscores the importance of using new technology to catalog this vast environment."

Ocean research organizations, like the Monterey Bay Aquarium Research Institute, are now vigilantly documenting and mapping the deep sea. Scientists want to shine a light — literally and figuratively — on what's down there. The implications of knowing are incalculable, particularly as deep sea mineral prospectors prepare to run tank-like industrial equipment across parts of the seafloor. For example, research expeditions have found that ocean life carries great potential for novel medicines. "Systematic searches for new drugs have shown that marine invertebrates produce more antibiotic, anti-cancer, and anti-inflammatory substances than any group of terrestrial organisms," notes the National Oceanic and Atmospheric Administration.