Hello, siphonophore: Scientists capture rare, purple deep-sea creature on camera

In June, researchers aboard the E/V Nautilus research vessel recorded a siphonophore swimming at the bottom of the Gulf of Mexico.

The video of the odd-looking, purple-blue sea creature went viral.

The difficult-to-spot siphonophore is not a jellyfish – although it does sting. Rather, it’s a “colonial animal,” comprised of “small, interdependent life-forms called zooids” that cannot reproduce or survive independently and essentially act as organs for the sea creature, National Geographic explained.

“Each zooid is an individual animal, but they all have adapted to fill specialized roles,” Katy Croff Bell, chief scientist of the Nautilus Exploration Program, wrote in an email to National Geographic from the ship. “For example, some are for protection, some are for eating, some are for reproduction, and some even ‘bioluminesce,’ or light up to attract food.”

A siphonophore can be as long as 50 metres, making it one of the longest creatures on the planet. The most famous siphonophore is the deadly Portuguese man o’ war.

“I’m not sure exactly what the population of siphonophores is globally (I wouldn’t be surprised if no one really knew) — but I do know that I’ve watched a LOT of underwater exploration and have seen a few siphonophores over the years, but [none] like that!” wrote Croff Bell.

After seeing the footage of the siphonophore, marine biologist Rebecca Helm wrote that she lives “for moments like this”:

“To me, the best part of science is stuff like this: seeing something that completely takes my breath away. Even after studying animals like this for the last five years, this video has me in awe. The animal captured in this footage, simply put, is stunning” Helm wrote for Deep Sea News.

Learn more about the mysterious siphonophore at Wired and National Geographic.