Hairy Porcelain Crab

Porcellana platycheles may attain a length of 15 millimetres (0.59 in). This species has wide, flattened front claws and two long antennae. It is greenish-brown on its back while the belly is off white. It has a small abdomen which it tucks under its carapace. The last pair of legs are highly reduced and are normally hidden making the crab appear to have only three pairs of walking legs. The body is flattened and the legs end in sharp claws, which are used to grip the underside of the rocks they live under. Porcelain crabs are more closely related to lobsters and squat lobsters than "true" crabs, a relationship hinted at by their long antennae.

Porcellana platycheles is distributed from Norway to the Canary Islands and throughout the Mediterranean. In Britain it is widely distributed around all coastlines from Shetland to Scilly.