A Mysterious Purple Orb at the Bottom of the Ocean [Video]

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American

The ocean is still full of stuff we’ve never seen before. Continuing my series of video highlights from this past summer's ocean exploration cruises, in this clip from the Nautilus Live expedition filmed in the Channel Islands off California, the explorers watching the feed struggle to identify an object they dub “Blobbus Purpulus”, which appears to be some sort of radioactive sci-fi artifact.

I love how their vacuum hose seems to be held together with duct tape. Take that, NASA.

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The staff at Nautilus write:

This unidentified purple orb stumped our scientists onboard. After sampling, it began to unfold to reveal two distinct lobes. After consulting with on shore scientists, the team thinks it may be a pleurobranch, a close relation to the nudibranch. Currently, none of the known species of California deep-sea pleurobranchs are purple, so this could be a new discovery.

Nudibranchs are ruffly, colorful, and frequently poisonous sea slugs, much beloved by divers who find them.

Pleurobranchs, also considered sea slugs, are more obscure. Like nudibranchs, they employ poisons. They can secrete toxins from their mantle to deter predators. But they also seem to be the shapeshifters of the sea slug world, contorting themselves not just into spheres (apparently) but also plastering themselves to rocks like sea slug pancakes, or disguising themselves as coral using rugged, contorted skin.

Here are two clips for your viewing pleasure of pleurobranchs showing off their amazing colors and interesting, pebbly textures as they slime along the sea floor. In an odd, sluggy way, they are really kind of adorable.