(Risso, 1816)
Description:
The body is dorso-ventrally flattened; up to 70 mm. The carapace is small and shield-like and is fused with only the first two thoracic segments. It is smooth and without spines and covers the posterior part of the head and the anterior part of the thorax. The bases of the eyes and antennae are covered by a rostral plate. The eye is large and has a bilobal cornea. Thoracic segments 5-8 extend clear of the carapace. The abdomen consists of six segments terminating in a 'tail fan" comprising a telson and two pairs of uropods. The sixth abdominal segment has spines on its dorsal, posterior edge. The telson bears three pairs of large marginal spines, its median posterior edge with a spinous cleft. The five anterior thoracic segments each have a pair of sub-chelate maxillipeds, the second pair being enormously enlarged and terminating in a raptorial claw, with 5 spines on its dactylus. The three posterior thoracic segments each have a pair of pereiopods. There are five pairs of pleopods on the abdomen, the gills being present on these appendages.
Habitat:
Subtidally to about 40 metres.
Distribution:
In the North Sea, it is restricted to the southern part. It occurs commonly in the Mediterranean but is not known from West Africa, although it is recorded on the Atlantic coast of Europe northwards to southern British waters.