Diamesa nowickiana Kownacki & Kownacka, 1975

Montagna, Matteo, Urbanelli, Sandra & Rossaro, Bruno, 2016, The species of the genus Diamesa (Diptera, Chironomidae) known to occur in Italian Alps and Apennines, Zootaxa 4193 (2), pp. 317-331 : 324-325

Diamesa nowickiana Kownacki & Kownacka, 1975

( Fig. 4 C, D)

Additions to the original description ( Kownacki & Kownacka 1975) are here provided (in parenthesis are reported the measures of the original description).

Adult male: length 4.8 mm (4.0 mm), wing length 3.674 mm (2.5 mm), wing width 1 mm, coloration brownish black.

Head dark brown, eyes haired, the hairs longer than ommatid, the head chaetotaxy as for the other species of the genus Diamesa . Antenna lost in the Amola specimen, in holotype with thirteen segments (pedicel: 120:72, 20:24, 28:28, 28:28, 32:40, 40:40, 44:476 µm), AR (0.87–0.92), all segments with bristles. Palp shorter than antenna, consisting of four segments: not measureable: 116: 158: 164 µm (80:128:112:160).

Hypopygium ( Fig. 4 C, D): Anal point short and wide, rounded apically, without bristles. IX abdominal segment with two groups of dorsal hairs symmetrically placed along the body line. Pars ventralis large. Aedeagal lobe characteristic, with a point in postero-lateral position. Gonocoxite with a superior volsella not projecting, almost square in shape, gonocoxite slightly concave in the middle part with a densely pubescent inferior volsella, enlarged in the middle, with two robust setae apically. Two strong setae in postero-median corner of gonocoxite.

Gonostylus widening towards the end, apical spine shorter than the back edge of the gonostylus, with welldeveloped sclerotized structures inside.

Systematic remarks. According to Kownacki & Kownacka (1980) the species belongs to the aberrata group, but the presence of hairy eyes suggests an affinity with the bertrami group. Diamesa nowickiana is easily separated from all the other species by the shape of the anal point.

Material collected: One pharate pupa with genitalia visible, Presena glacial stream, 13IX1990; one male, Amola glacier 14VIII2014.

Figures

FIGURE 4. A, Diamesa martae Kownacki & Kownacka, male genitalia; B I, anal point, B II, sternapodeme and pars ventralis, B III, inferior volsella, B IV, gonostylus; C, Diamesa nowickiana Kownacki & Kownacka, male genitalia; D I, anal point, D II, pars ventralis, D III, phallapodeme and inferior volsella, D IV, inferior volsella and gonostylus.