Diamesa cinerella, Meigen, 1835

Key to species of Diamesa cinerella View in CoL group for adult males

1. Antenna with 8 flagellomeres............................................................................ 2

- Antenna with 13 flagellomeres........................................................................... 3

2. Basimedial setae of gonocoxite long and numerous.............................. D. kasymovi Kownacki et Kownacka View in CoL

- Gonocoxite without basimedial setae....................................................... D. tsutsuii Tokunaga View in CoL

3. Antenna plume’s setae104–108 μm long and sparse (2–4 setae on flagellomere) ( Figs 3–4 View FIGURES 1–7 )........................... 4

- Antennal plume’s setae, 200–689 μm long, little reduced (3–6 setae on flagellomere) ( Figs. 1–2, 5 View FIGURES 1–7 ).................... 5

4. Gonocoxite with 20–26 basimedial setae, 80–100 μm long ( Fig. 22 View FIGURES 19–22 ). Gonostylus wider basally and gradually narrowing towards apex ( Figs 19–20 View FIGURES 19–22 ).................................................................... D. lavillei Serra-Tosio View in CoL

- Gonocoxite with 4–7 basimedial setae, 40–44 μm long ( Fig. 25 View FIGURES 23–26 ). Gonostylus with inflated basal part and narrowing distal ( Fig. 26 View FIGURES 23–26 ).............................................................................. D. hyperborea Holmgren View in CoL

5. Inferior volsella with two branches, the longer branch bearing a tuft of longer setae at the tip ( Figs 31–32 View FIGURES 31–34 )...................................................................................................... D. tonsa Haliday View in CoL

- Inferior volsella simple................................................................................. 6

6. Inferior volsella in the form of a wide lobe covered with short setae ( Figs 15–17 View FIGURES 15–18 ). Gonocoxite with 6–8 basimedial setae, 68–100 μm long ( Fig. 18 View FIGURES 15–18 )................................................................ D. cinerella Meigen View in CoL

- Inferior volsella not shaped as above. Gonocoxite with more than 13 basimedial setae............................... 7

7. Total length 3.6–4.2. AR 0.62–0.67. Gonocoxite with 13–17 basimedial setae ( Fig. 24 View FIGURES 23–26 )........... D. hamaticornis Kieffer View in CoL

- Total length 3.0–3.5. AR 0.39–0.40. Gonocoxite with 26–30 basimedial setae ( Fig. 28 View FIGURES 27–30 )............ D. soktoshensis sp. nov.