Very common around the UK (but less so in the south west) on the lower shore and to a depth of 50m. The Great Spider Crab, Hyas araneus has a pear-shaped body up to 10cms in length. The carapace is reddish-brown and the underparts off-white. The two frontal claws are fairly insignificant and often kept folded under the body. It inhabits a wide variety of habitats from vertical rock walls to rough ground and is frequently seen climbing up kelp plants. The carapace is regularly covered in encrusting animal life which breaks up the outline providing a measure of protection from predators. Like some other spider crabs it is often referred to generically as a Decorator Crab. Also called the Sea Toad in some older identification books.
St. Abbs Marine Reserve, North Sea