Eurydice affinis

Hansen, 1905

Body more or less semicylindrical in shape, the eyes are lateral and of normal size. Antenna 1 scarcely reaching the anterior lateral angle of the pereion; peduncle with article 3 scarcely longer than article 2; flagellum thick in male, slender in female. Antenna 2 peduncle of 4 distinct articles. Maxillipedes without coupling hooks on the inner border. The dactyls of pereiopods 1 to 3 are not markedly larger than those of pereiopods 4 to 7. Distinct coxal plates on pereion segments 2 to 7. Coxal plates of pereion segments 6 and 7 with the posterior angles sharp but not produced into processes. Pleon with five distinct segments plus one (the uropodal segment) fused with the telson. Pleon segment 5 not markedly reduced, with the lateral borders contributing to the body outline. Pleopod 1 with both rami thinly chitinised and fringed with setae. Pleotelson similar to Eurydice pulchra : posterior border fairly broadly rounded, with two small spines at each corner among the fairly long plumose setae. Uropods lateral, not arching dorsally and with the pleotelson forming a terminal fan. Uropod peduncle not markedly produced backwards alongside inner border of endopod; articulation between peduncle and endopod short.
Males recognizable at just over 2 mm body length, ranging to about 5 mm; females 2-6 mm. Colour pale, with black chromatophores restricted to dorsal body surface; abdomen yellowish.

Among Eurydice pulchra in intertidal sand.

In Britain so far known mainly in the Bristol Channel area, on the coasts of South Wales and north coasts of Devon and Cornwall, but recently found in North Wales. Also recorded on the Dutch coast (Wolff, 1966), but predominantly in the Mediterranean and on the Atlantic coasts of France.