Liljeborg, 1852
Description:
Urosome segments 1 to 3 with weakly developed dorsal humps, spine groups with several long setae. Epimeral plates 2 and 3 subquadrate, posterior margin with several long setae, set in notches. Head with the lateral lobes broadly truncated, post-antennal sinus deep. Eyes moderately large, elongate kidney-shaped. Antenna 1 peduncle sparsely setose, article 1 shorter than articles 2 and 3 together; accessory flagellum a little shorter than the peduncle article 2, about 5 or 6-articulate. Antenna 2 moderately setose, flagellum with calceoli in male. Mandible palp article 1 with one or two apical setae, article 3 with one setal group on the outer surface, ventral setae comb-like, not graduated. Male gnathopod 1 propodus palm about straight with the median palmar spine equal spaced with the row of angle spines, proximal posterior margin densely setose. Male gnathopod 2 propodus much broader than in gnathopod 1 and the palm less strongly oblique, median palmar spine forming a continuous row with three or four angle spines, proximal posterior margin densely setose. Female gnathopod 1 propodus suboval, palm oblique, convex, margin with four well spaced spines. Female gnathopod 2 propodus rectangular, palm transverse, margin with four well spaced spines. Pereiopods densely setose, less densely setose in female than in male; setae much longer than the associated spines. Pereiopods 5 to 7 slender, basis with the posterodistal angle freely produced, angle without spines but with a group of subangular setae. Uropod 3 inner ramus more slender than the outer one and about one-half to two-thirds of its length, margins extremely densely setose, inner marginal setae plumose; setae less dense in female. Telson with each lobe with four apical spines, nil or one subapical spine, two or three lateral spines, each group with several long setae.
Size:
Up to 22 mm in male, 16 mm in female.
Colour:
Dark greenish or brownish, with pink patches on sides of the pleon.
Habitat:
A brackish-water species with wide salinity tolerance: found on rocky shores in pools near to high water with freshwater influence, in estuaries amongst vegetation and in freshwater streams and lakes.
Distribution:
North East Atlantic, North Sea, Bothnian Bay.