Attheyella (Brehmiella) trispinosa (Brady, 1880)

(Figs 10–11)

Location, ecology. The species was found among aquatic vegetation in lakes and rivers. High numbers of A. trispinosa up to 160 indiv. l −1 were recorded in Stratiotes aloides habitats in Lake Tyrkło and Bełdany in the Masurian Lakeland (Karpowicz et al. 2016). Many male-female tandems were observed (Fig. 11). In the pre-copulatory (phase preceding mating) the male harpacticoid grasps the caudal rami of the female with its first antenna (Glatzel 1988).

General distribution and biology. Lowland water bodies of Europe, North Africa and Asia (Borutzky 1952). Widespread in Poland (Błędzki 2004). The range of the subgenus Brehmiella is mostly restricted to the Holarctic region (Borutzky 1952).

D i s t i n g ui s h i n g f e a t ur e s. Relatively large species, length of female without caudal setae 0.72–0.84 mm. Caudal rami short, slightly tapering distally. Endopodite and exopodite of P1 three-segmented (Fig. 10). First segment of P1 endopodite as long as whole exopodite of P1 (Fig. 10). Diagnostic features of the species include also structure of P 5 in both sexes.