Parapsectra mendli Reiss, 1983

Giłka, Wojciech & Jażdżewska, Natalia, 2010, A systematic review of the genus Parapsectra Reiss (Diptera: Chironomidae: Tanytarsini) with description of a new species from Poland, Zootaxa 2350, pp. 1-21 : 8-10

Parapsectra mendli Reiss, 1983

( Figures 3 , 15–18 , 36, 37 )

Material examined. POLAND. Czarna Tama at Lake Spierewnik near Tuchola, sweep net, at limnocrene, 20 April 2008, 3 males, 28 April 2009, 39 males, 21 July 2009, 5 males, WG. Wysocki Młyn near Tuchola, sweep net, at helocrene, 28 April 2009, 7 males, WG.

Diagnostic description. Adult male (measurements in Tables 3 and 8).

Colouration. Antennal pedicel, scutal stripes, postnotum and sternum dark brown to fuscous; antennal flagellum, head capsule, scutellum, haltere, legs, ground colour of thorax and abdomen including hypopygium olive to dark brown; wing with brownish undertone, with C, M and radial veins darker, brownish. Head. Antenna with 13 well-separated flagellomeres. Frontal tubercles present, sometimes very short and visible as tiny swellings. Third palpomere usually longer than fourth. Wing. Sc, M, R2+3, short proximal section of M1+2 and 1/4 proximal part of Cu bare, remaining veins with macrotrichia. FCu slightly distal of RM. RM relatively long. Membrane below An with sparse macrotrichia. Anal lobe of wing reduced ( Fig. 3 ). Legs. Spur of fore tibia straight or slightly bent, 12–25 μm long. Combs of mid and hind tibiae usually slightly separated, if widely separated - number of teeth reduced; each tibia with 20–35 teeth 12–20 μm long (mid leg) and 25–45 teeth 16–25 μm long (hind leg); sometimes each comb bears single, somewhat longer spur-like tooth. For lengths of leg segments see Table 3 and Reiss (1983; presumably mean values given).

fe ti ta1 ta2 ta3 ta4 ta5 Hypopygium. Gonostylus stout, widest in half length, tapering to rounded apex, variable in shape ( Figs 15, 16 ). Anal tergite with long, separated bands of V-type; lateral teeth present; anal point slender, acute, bearing short crests; entire area surrounding base of anal point covered with microtrichia ( Fig. 15 ). Superior volsella with slender apical prolongation and anteromedian margin concave, bearing dorsal setae placed in row, with proximal seta somewhat distant; digitus well-developed, apically pointed, reaching at least half length of superior volsella; Micropsectra -seta placed on short conical tubercle ( Figs 15, 17 ). Median volsella with relatively long, slightly bent and laterally directed stem bearing c. 20 strongly curved spoon-shaped lamellae arranged irregularly ( Fig. 18 ). Inferior volsella long, reaching half length of gonostylus, straight or slightly bent and directed medially, with slight transversal protrusion and rounded apex ( Fig. 15 , 36, 37 ).

Adult female, pupa and larva: unknown.

Discussion. Characters which best separate adult male of Parapsectra mendli from other Parapsectra are the acute hypopygial anal point as well as the superior volsella with its slender apical prolongation and the concave anteromedian margin ( Figs 15, 17 ). The tubercle placed at base of the superior volsella bearing the Micropsectra -seta is short and broadly conical in P. mendli , whereas it is prominent, usually cylindrical in other Parapsectra . The median volsella, bearing numerous small and strongly curved spoon-shaped lamellae, is also a unique character within the genus ( Fig. 18 ).

Although immatures of P. mendli are unknown, the species is presumed to be a cold-adapted stenothermic inhabitant of springs ( Reiss 1983). Adults of the species have been so far recorded at two sites, in April ( Reiss 1983) and June ( Ekrem et al. 2007). In this study, swarming males were observed at two other sites in the Eastern Pomerania (N Poland), in the closest vicinity of springs, and - in abundance - at a limnocrene. The adults were collected in April and July, but were not recorded in May and June. The specimens sampled from the same site in summer differ in having shorter wing (1.55–1.60 vs 1.75–2.05 mm in specimens collected in spring), lower AR (0.67–0.70 vs 0.72–0.79), higher LR (1.45–1.47 vs 1.33–1.36), and probably belonged to the second generation. Body measurements of the specimens examined are compatible with the original description ( Reiss 1983), except for wing, which - in the original description - was presumably measured from the base, rather than from the arculus, to the tip.

Figures

FIGURES 1 – 4. Wing of male. 1: Parapsectra bumasta sp. n., 2: P. chionophila, 3: P. m e n d l i, 4: P. nana.

FIGURES 15 – 18. Parapsectra mendli, male. 15: hypopygium, 16: gonostylus (variation), 17: superior volsella and digitus (variation), 18: median volsella (magnified x 2 in comparison with hypopygium).

FIGURES 32 – 41. Hypopygial inferior volsella and inner margin of coxite. 32, 33: Parapsectra bumasta sp. n.; 34, 35: P. chionophila; 36, 37: P. m e n d l i; 38: P. nana; 39: P. styriaca; 40: P. uliginosa; 41: P. wagneri.

Tables

TABLE 3. Length (μm) of leg segments of male Parapsectra mendli.

p1 800–1005 (910)	550–735 (655)	810–990 (890)	410–500 (465)	310–390 (350)	220–280 (255)	120–155 (140)
p2 755–965 (870)	655–795 (735)	360–455 (410)	215–270 (245)	155–205 (185)	105–145 (130)	80–110 (100)
p3 925–1175 (1070)	825–1065 (965)	515–685 (610)	330–410 (380)	245–310 (285)	155–200 (180)	95–125 (115)