G.O. Sars, 1897
Description
Body oblong oval. Antenna 1 more or less reaching the distal end of article 3 of the peduncle of antenna 2; antenna 2 flagellum longer than peduncle, 1/4 to 1/5 of the body length.
Cephalon subquadrate, eyes dorso- lateral, prominent. Maxillipedal palp of four articles. Coxal plates wide, extending the whole length of each segment from pereional segment 2 or 3 to 7. Pereiopods all more or less alike. Pleon of two complete segments, and one partial suture in the pleotelson. Pleotelson with the sides fairly straight and converging posteriorly; posterior border characterised by a median obtuse tooth, and obtusely rounded lateral shoulders; keeled. Uropods uniramous.
Colour often uniformly brownish, sometimes with white longitudinal lateral markings, and occasionally with white marbling over the whole dorsal surface; adult females mostly darker than males.
Size
Males recognisable from about 8 mm, ranging to nearly 30 mm; adult females range from 10 to 16 mm.
Depth range/habitat
Generally sublittoral on accumulations of detached algae or fish waste, but also between tidemarks, usually in company with Idotea balthica and Idotea emarginata among cast up drift weed; mayt be found free swimming.
Distribution in the North Sea
All North Sea.
Distribution
On fully marine European coasts from Norway to France.