Decorator Crab

''Achaeus spinosus'' is a small decapod which belongs to the large family of the Inachidae or the spider crabs.
The carapace has an oval shape and does not exceed 4 centimetres or 1.6 inches in length. The pedunculate eyes are red. The whole whitish body is thickly covered with fine hairs which help to fix some pieces of sponge or fixed hydroids for camouflage.