Crabs Camouflage Their Own Lunch With Algi

Notomithrax ursus is a species of crab that likes to eat seaweed. The algie on its back will help it blend with its environment, make it look like a bunch of seaweed rather than a crab. But then also, it can eat that seaweed if it gets hungry. It's like an army sniper in one of those gilly suits - but they insisted on only camouflaging themselves with their favourite leafy greens.