Christmas Cactus?

Image: Alfiero Brisotto
Alcyonium palmatum

It's a Christmas Cactus! I think... But what's it doing at the bottom of the sea?

OK, fine! It's not a cactus. It's a coral. Specifically, it's Alcyonium palmatum, a kind of soft coral found on the European side of the Atlantic and the Mediterranean Sea.

Image: Alfiero Brisotto

Being soft corals they don't have the tough, stony skeletons that some others have. Instead they're rather leathery.

Inside this leathery tissue are the siphonozooids, which are polyps that pump water into the colony and ensure the whole thing doesn't collapse under it's own weight.

Image: Alfiero Brisotto

At the surface are the autozooids, the feeding polyps. When not in use, they are retracted into the red skin to keep them safe and secure.

Come dinner time, those little white polyps emerge and spread their eight, delicate tentacles into the current and capture tiny morsels of food.

Image: Alfiero Brisotto

Because Christmas doesn't really begin until dinner time!