(Pennant, 1777)
Description:
Carapace slightly broader than long, dorsal surface tuberculate, tubercles prominent on posterior half; protogastric region concave, posterior epibranchial and anterior mesobranchial particularly elevated, cardiac swollen. Third maxilliped narrowing anteriorly. Antero-lateral margins of carapace proximally sinuous, distally convex and tuberculate. Chelipeds equal in size, pereiopods 2-5 tuberculate; abdominal segments 3-6 fused. Male chelipeds longer and more robust than in female; apex of first pleopod with a crown of spines.
Size:
Carapace length up to 13 (17) mm.
Habitat:
Depth range from rarely intertidal to 150 metres. Common, on gravel and stony bottoms. Probably ovigerous throughout year, larvae from January-November.
Colour:
Variable, carapace and pereiopods light yellowish-orange to deep reddish-brown, sometimes with white bands or spots.
Distribution:
Shetland, Orkney, Moray Firth, Aberdeen, Firth of Forth, Northumberland, Yorkshire, East Channel, Wight, Portland, Channel Isles, Plymouth, Scilly Isles, Bristol Channel, Isle of Man, Dublin, Belfast, Clyde & Argyll, Mayo, Galway Bay, Fastnet, Cork.