Bryozoa Nudibranch

Image: Donna Pomeroy

This has to be one of the more eye-bending examples of camouflage out there.

It might be difficult to believe when it's so lacy and frilly and, er, uncooperatively resting on a dark background upon which it sticks out like an ornately gloved thumb...

Image: cassidy

But it works a lot better on the right background. Which, in this case, is Bryozoa.

Bryozoans, also known as Moss Animals or Ectoprocts (good alien name there) are tiny, colonial animals that are not coral... they just share a few ideas. Bryozoan colonies can be shaped like little bushes or curly lettuce but their most common form is a simple encrusting layer on stone or seaweed. The colony looks like a tiny brick wall or cobblestone street, except each cobblestone is actually a hole with a monster inside it. You'd think someone would complain about roads like that. You know its bad when the potholes have become residential.

Video: SpinelessStudio

The monsters in question are teeny-tiny creatures who catch the tiniest crumbs of food from the water using their crown of tentacles. For the Bryozoa Nudibranch, this sounds delicious.

There are several species of Bryozoa Nudibranch, all occupying the genus Corambe and found crawling all over Bryozoans in warm places like the Caribbean and South Africa. They themselves are tiny at about 1 or 2 cm (0.4 to 0.8 in) long and, with a bit of transparency and a few hazily drawn white lines, they quickly melt away as they plough their way through their chosen meal.

It's sort of eerie to see them slide over the cobblestones like a piece of curved glass. It feels like they should disappear the moment I blink and look again. I guess that what makes it such great camouflage: you know you're onto a winner when it makes everyone around you question their sanity.