New data to the knowledge on the Harpacticoida (Crustacea, Copepoda) fauna in Poland Author KARPOWICZ, Maciej text Fragmenta Faunistica 2016 59 2 87 98 http://dx.doi.org/10.3161/00159301ff2016.59.2.087 journal article 20489 10.3161/00159301FF2016.59.2.087 c9f13a5a-2221-4314-9b61-38fbb6c514ba 2391-5846 6251956 Nitokra hibernica (Brady, 1880) (Figs 4–7) Lo cat io n, ecolo gy. Nitokra hibernica was common found on the surface of zebra mussel ( Dreissena polymorpha ) from Lake Mikołajki in the Masurian Lakeland. Both females (some with egg sacs) and males were observed. G e n e r a l d i s t r i b u t i o n a n d b i o l o g y. Widespread in Europe and Asia, mainly in large lakes and rivers. Chappuis (1927) observed N. hibernica in the gill cavity of the common crayfish. Jakubisiak (1929) found the species in the water system of Poznan city. Those specimens slightly differed from the typical form and were named by Jakubisiak (1929) as Nitocra hibernica var. hyalina (see also Borutzky 1952 ). D i s t i n g u i s h i n g f e a t u r e s. Body length without caudal setae about 0.65 mm . Caudal rami as long as wide (Fig. 4). Antennule eight-segmented with second segment bolded (Fig. 5). Anal plate semicircular and armed with spinules (Fig. 6). Both rami of P1 – P4 threesegmented. Inner lobe of basal segment of P5 triangular-shaped, distal segment large and ovate with 6 setae and bearing several spinules on both medial and lateral margins (Fig. 7).