A close-up of a medium-sized
sponge crab, less than a foot wide overall. Sponge crabs
often use their rearmost pair of legs to grasp a piece of
live sponge, which they carry around over their backs as
part of their disguise. The furry appearance is from
algae growth, which also helps it blend into its
environment and hide from predators, such as the octopus.
Like many of the "disguised" crabs, sponge
crabs are generally slow movers.