"Decorator crabs" refers to a type of crab that camouflages itself by attaching things like algae, shells, or debris to its body. This helps the crab blend in with its surroundings and hide from predators. Full definition
The highlights were plentiful, ranging from Pygmy Cuttlefish, Papuan and Tasseled Scorpionfish, Decorator Crab ad a few different nudibranchs and flatworms. (aggressor.com)
The bull kelp and winged kelp were covered in patches of a colonial organism called a lacy bryozoan and decorator crabs clung to the blades. (uncruise.com)
There are splendid decorator crabs, the intelligent red octopus, and red and white banded boxer shrimps. (divetheworldthailand.com)