Parapsectra nana Meigen 1818

Parapsectra nana (Meigen, 1818)

(Figures 4, 19–21, 38)

Material examined. POLAND. KoŻyczkowo near Chmielno, 31 May 1997, sweep net, 3 males, ES. Sudety Mts., Szklarska Poręba, 5 August 1982, sweep net, 3 males, RSz. Tatra Mts., Dolina Roztoki, 1200 m a.s.l., 6 August 1981, sweep net, 1 male, RSz. Zakopane-Oberconiówka, 900 m a.s.l., 7 August 1981, sweep net, at peat bog, 1 male, RSz. BULGARIA. Rila Mts., Skakavica near Sapareva Banja, 1580 m a.s.l., 20 July 1976, sweep net, at waterfall, 4 males, RSz. FINLAND. Sarmitunturi near Vanhapää (Inari distr.), c. 13 km west of the Russian border, 3 June–27 August 2004, Malaise trap, at spring brooks and small lakes, 3 males, JS. NORWAY. Semska (Arctic Circle), 680 m a.s.l., 6 July 2006, sweep net, at peat pools, 1 male, WG.

Diagnostic description. Adult male (measurements in Table 4 and 8).

Colouration. Antennal pedicel, postnotum and sternum brown; scutal stripes orange to brown, antennal flagellum and legs olive brown; head capsule, scutellum, haltere, ground colour of thorax and abdomen including hypopygium green to olive-green; wing with yellowish undertone, with C, M and radial veins slightly darker, brownish. Head. Antenna with 13 well separated flagellomeres. Frontal tubercles rarely present as tiny swellings. Third palpomere usually shorter than fourth. Wing. Sc, M, R2+3, very short proximal section of M1+2 and 1/4 proximal part of Cu bare, remaining veins with macrotrichia. FCu under RM. RM long. Membrane below An with numerous and dense macrotrichia. Anal lobe of wing relatively well developed (Fig. 4). Legs. Spur of fore tibia straight, 8–12 μm long, often reduced or absent (n = 2). Combs of mid and hind tibiae slightly separated, each tibia with 22–35 teeth 10–15 μm long (mid leg) and 30–35 teeth 12–16 μm long (hind leg); sometimes each comb bearing single, somewhat longer spur-like tooth.

Hypopygium. Gonostylus slender, nearly twice as long as gonocoxite, regularly tapering to narrow tip. Anal tergite with long separated bands of V-type; lateral teeth absent; anal point broad at base, short and apically rounded, bearing long thin crests; microtrichia-free area surrounding base of anal point small (Fig. 19). Superior volsella triangular, apically pointed, with anteromedian margin straight, bearing setal protuberances; digitus well developed, usually reaching slightly beyond half length of superior volsella, variable in shape but usually acute; Micropsectra -seta placed on tall cylindrical tubercle (Figs 19, 20). Median volsella moderately long, with stem bearing c. 20 small spoon-shaped lamellae placed in 2–3 irregular rows apically (Fig. 21). Inferior volsella short and straight, with very slightly swollen distal half, apically rounded Pupa: Reiss (1969b), Langton (1991); adult female and larva: unknown.

Discussion. Due to the set of characters discussed above, Parapsectra nana, P. b u m a s t a and P. chionophila form a putative species group. The characters which best separate P. nana from its sibling species are the slender gonostylus, nearly twice as long as gonocoxite, and the short and straight inferior volsella (Figs 19, 38).

P. nana is associated with cold-water habitats. The specimens examined were collected in northern spring brooks, peat pools and small lakes, and at a waterfall and peat bogs in uplands and mountains of central and eastern Europe.