Rostrum slightly downcurved, little shorter than antennular peduncle and slightly deeper than in Caridion gordoni; five to seven dorsal teeth, one ventral tooth.
Carapace with antennal spine.
Stylocerite narrow, acutely pointed, 0.5 -0.66 x length of antennular peduncle.
Scaphocerite outer border straight, apex less acute than in Caridion gordoni, apical spine not exceeding lamellar portion. Antennal flagellum normally as long as body, sometimes a little shorter. Third maxilliped only slightly longer than scaphocerite; epipod and exopod present.
Mandible with molar and incisor process, and three-segmented palp.
Carpus of pereiopod 2 two-segmented, chelae long and slender. Pereiopods 1-4 with epipods, pereiopod 5 with reduced setobranch. Pleonite 4 with ventro-posterior tooth in both sexes.
Telson with two pairs of lateral spines.
Very similar to Caridion gordoni. Any Caridion found on the shore or in shallow water usually proves to be Caridion steveni.
Length up to 27 mm.
Red, with diffuse yellow; scattered with red, small chromatophores.
Down to about 30 metres. Usually a littoral species, occurring under stones and amongst algae at ELWS. It is not certain whether this species never swims up into the water column. Ovigerous females occur from January to May.
Distribution in the North Sea:
Northern North Sea, British NE coasts, Skagerrak.
Its full range is unknown, although its southern limit is probably SW England, since Bourdon (1965) records only larval stages at Roscoff and Zariquiey Alvarez (1968) makes no mention of it from Spanish shores. The northern limits are also unknown.