Tetragoneura

Polevoi, Alexei & Jakovlev, Jevgeni, 2011, A review of the European species of the genus Tetragoneura Winnertz (Diptera: Mycetophilidae), Zootaxa 3062, pp. 1-12 : 10

Key to European species of Tetragoneura

1. R4 and small cell absent. Sensory organ on dorsal side of male mid tibia present. Mid tibia in male with one spur. Tergite 9 at least half as high as gonocoxites, cerci reduced.............................................................. 2

- R4 normally developed forming elongated small cell (small cell may be reduced or even absent in one or both wings in T.sylvatica ). Sensory organ on dorsal side of male mid tibia not developed. Mid tibia in male with two spurs. Tergite 9 not higher than 1/3 of gonocoxites, mostly as a narrow transverse stripe, cerci well developed.................................. 3

2. Gonostylus relatively short with apical hook. Tergite 9 with submedian appendages ( Fig. 1 : A–C). Female terminalia as in Fig. 3 A, B................................................................... Tetragoneura ambigua Grzegorzek

- Gonostylus elongated, angled the middle. Tergite 9 without submedian appendages ( Fig. 1 : D–F)................................................................................................... Tetragoneura pudogensis sp. n.

3. Tergite 9 divided into two separate sclerites. Gonostylus attenuated to apex, with curved seta at base ( Fig. 2 : E, F). Female terminalia as in Fig. 3 : C, D....................................................... Tetragoneura ruuhijarvii sp. n.

- Tergite 9 integrate. Gonostylys different.................................................................... 4

4. Gonostilus bilobed ( Fig. 2 : C, D)................................................ Tetragoneura obirata Plassmann

- Gonostylus ovate with strongly sclerotised, blade-like sub-apical process ( Fig. 2 : A, B). Female terminalia as in Fig. 3 : E, E.............................................................................. Tetragoneura sylvatica Curtis

Figures

FIGURE 1. Male terminalia. A. T. ambigua, dorsal view. B. T. ambigua, ventral view. C. T. ambigua, lateral view. D. T. pudogensis sp. n., dorsal view. E. T. pudogensis sp. n., ventral view. F. T. pudogensis sp. n., lateral view. Scale bars = 0.2 mm. Abbreviations: ae = aedeagus, gc = gonocoxite, gst = gonostylus, tg = tergite, sml = submedian lobe.

FIGURE 2. Male terminalia. A. T. sylvatica, dorsal view. B. T. sylvatica, ventral view. C. T. obirata, dorsal view. D. T. obirata, ventral view. E. T. ruuhijarvii sp. n., dorsal view. F. T. ruuhijarvii sp. n., ventral view. Scale bars = 0.2 mm. Abbreviations: ca = complementary appendage, cerc = cercus, gc = gonocoxite, gst = gonostylus, tg = tergite, sap = subapical process, sml = submedian lobe.

FIGURE 3. Female terminalia. A. T. ambigua, lateral view. B. T. ambigua, ventral view. C. T. ruuhijarvii sp. n., lateral view. D. T. ruuhijarvii sp. n., ventral view. E. T. sylvatica, lateral view. F. T. sylvatica, ventral view. Scale bars = 0.2 mm. Abbreviations: cerc = cercus, gc = gonocoxite, hyp = hypoproct, tg = tergite.