Cold Sea Balloon... OF DEATH!

It's a drawstring bag of death! It's a bin liner of doom!

No, it's... er...

Space Invaders 3D

We first saw this flimsy sack of alienage back in 2012, when people who had no idea what they were looking at suggested it might be a placenta of whale.

Thankfully, more knowledgeable folks stepped in to clarify. It was actually a Deepstaria. In other words, a jellyfish of deep sea.

Jellyfish are weird. Everyone knows that. They don't have a face. They don't have flippers or fins or anything like that, either but... no face! I mean... How...? Never mind. Jellyfish is as jellyfish does, and they do it with an abundance of tentacles and a pulsing bell.

So what can poor, deep sea jellies do to make themselves even weirder?

Here's one solution: ease up on the tentacles and max out the bell until you're essentially a gigantic bag. Sorted!

Video: EVNautilus

Deepstaria jellyfish can reach up to a metre (3.3 ft) across and have completely given up on trying to catch a tasty morsel at the end of a tentacle. Instead, their entire body is one enormous trap. Anything unfortunate enough to swim into that gigantic bell finds their world slowly shrinking into nothing as the bell closes around them like a drawstring bag.

Once successfully bagged, it's thought that the prey would try to escape and only succeed in bumping into stinging cells (of death) on the inner side of the bell. Once they're weak or paralyzed, the body could be conveyed by waving cilia to its final resting place: the mouth at the top of the jellyfish.

Deepstaria are covered in a kind of mesh made up of canals that convey nutrients throughout its vast body, and you know, I have to admit it looks quite attractive. If my bin liner could absorb banana peels and look good doing it, I don't think I'd complain.