Rhamphomyia Meigen 1822

Key to male Rhamphomyia of the Canadian Arctic Islands, Greenland and Iceland

1 Prosternum clothed entirely with white to brownish silky, hair-like setae (Fig. 3D); sternite 6 with cluster of strong golden setae; sternite 7 with pair of horn-like projections ventrally (Fig. 3C).................... R. (Ctenempis) albopilosa Coquillett

- Prosternum bare; sternite 6 without row of golden setae; sternite 7 unmodified or modified different than above.......... 2

2 Cerci directed anteriorly (Figs 6A, 9C, 12B, 15B) (subgenus Dasyrhamphomyia)................................... 3

- Cerci directed posteriorly............................................................................... 6

3 Thorax short haired (setae shorter than gaps between rows) with acrostichals and dorsocentrals 1–2 serial, with brown vittae beneath rows; cerci with dark apex, with left cercus overlapping right at tip (Figs 12B, C); hind tibia with anteroventral row of dark, stout, spine-like setae shorter than half tibial width.................................. R. (D.) leptidiformis Frey

- Thorax long haired (setae longer than gaps between rows) with acrostichals and dorsocentrals 2–4 serial, without brown vittae beneath rows; cerci not darkened at apex, with right cercus overlapping left at tip (Figs 9D, 15C); hind tibia without anteroventral row of dark, stout, spine-like setae..................................................................... 4

4 Cerci pale, elongate, extending to tergite 3, overlapping subapically in addition to apical overlap (Figs 15B, C)........................................................................................... R. (D.) nigrita Zetterstedt

- Cerci brownish to black, shorter, extending to tergite 5, only overlapping apically (Figs 6A, 9C)....................... 5

5 Dichoptic; abdomen with setae longer than length of abdominal tergites; cerci blackish (Fig. 6A); hind tibia and femur with pronounced fine, pale ventral pubescence (Fig. 6C).................................... R. (D.) erinacioides Malloch

- Holoptic; abdomen with setae shorter than length of abdominal tergites; cerci pale brown (Fig. 9C); hind tibia and femur with long setae beneath (Fig. 9A)...................................................... R. (D.) hovgaardii Holmgren

6 Wing without dm-m crossvein (cell dm open) (Fig. 62C); scutum with shiny vittae................................................................................................. R. (Pararhamphomyia) diversipennis Becker

- Wing with dm-m crossvein (cell dm closed), sometimes dm-m crossvein or M 2 base absent in R. (P.) omissinervis Becker; scutum without shiny vittae............................................................................. 7

7 Cercus with distinctive finger-like projection dorsally near base (Figs 53B, 60A)................................... 8

- Upper margins of cercus without finger-like projections....................................................... 9

8 Large species (wing length more than 5 mm); phallus curvature occurring before folding into epandrium; cercal finger-like projection stout (Fig. 53B); mid tibia with at least 3 preapical anteroventral and posteroventral setae dark, stout, spine-like..................................................................................... R. hirtula Zetterstedt

- Small species (wing length less than 4 mm); phallus curvature hidden within epandrium; cercal finger-like projection slim, short, less than half cercal length (Fig. 60A); mid tibia with 2 anterodorsals and 2 posterodorsals longer than twice tibial width................................................................................ R. setosa Coquillett

9 Tergite 8 long, subequal to length of epandrium (Iceland only) (Fig. 46B).................... R. (P.) simplex Zetterstedt

- Tergite 8 shorter than length of epandrium................................................................ 10

10 Subepandrial sclerite prolonged into pair of medioposterior lobes beneath cerci (Figs 31C, 28A, 25C, 34A, 36C, 38C, 40A).................................................................................................... 11

- Cercus without pair of subepandrial lobes beneath.......................................................... 17

11 Apex of subepandrial lobe forked....................................................................... 12

- Apex of subepandrial lobe unforked..................................................................... 14

12 Phallus stout, looping dorsally above cercus and epandrium; apex of phallus expanded with ridge of teeth-like projections (Figs 28A, B).............................................................................. R. (P.) helleni Frey

- Phallus slender, filamentous apically, extending slightly beyond epandrium; tip of phallus slender, tapered, lacking teeth-like projections......................................................................................... 13

13 Fore tarsomere 1 swollen, slightly broader than width of fore tibia at apex (Fig. 31A); tergite 5 without stout posterolateral setae; subepandrial lobe with outer finger-like process lacking apical seta, longer than inner lobe (Figs 31 C-E)............................................................................................ R. (P.) hilariformis Frey

- Fore tarsomere 1 slender, narrower than width of fore tibia at apex; tergite 5 with several closely set stout posterolateral setae (Fig. 38B); subepandrial lobe with slender, outer finger-like process bearing 1 very long, fine, black seta (Figs 38C, D).................................................... R. (P.) lymaniana Sinclair, Vajda, Saigusa & Shamshev sp. nov.

14 Phallus not forming loops.............................................................................. 15

- Phallus forming loops................................................................................. 16

15 Hind tibia with some anterodorsal, posterodorsal and dorsal setae more than 2X tibial width (Fig. 25B); apex of subepandrial lobe rounded (Figs 25A, C)............................ R. (P.) frigida Sinclair, Vajda, Saigusa & Shamshev sp. nov.

- Hind tibia with anterodorsal, posterodorsal and dorsal setae shorter than 2X tibial width (Fig. 34B); apex of subepandrial lobe pointed (Fig. 34A)....................................................................... R. (P.) hoeli Frey

16 Hind tibia clavate (Fig. 36D); hind tarsomere 1 shorter than length of tarsomeres 2–4 combined (Fig. 36D)............................................................................................ R. (P.) kjellmanii Holmgren

- Hind tibia not clavate (Fig. 40B); hind tarsomere 1 longer than length of tarsomeres 2–4 combined (Fig. 40B)........................................................................................... R. (P.) omissinervis Becker

17 Phallus hidden within epandrium, leaving only base visible (Fig. 17B)................................................................................. R. (Eorhamphomyia) shewelli Sinclair, Vajda, Saigusa & Shamshev sp. nov.

- Phallus slim to hair-like, usually extending farther than length of epandrium, and often with curvatures................ 18

18 Phallus with distinct loop on apical half around apex of epandrium (Figs 51C, 57A)............................... 19

- Phallus without loop, gradually curved................................................................... 20

19 Sternite 8 with stout, “horn-like” lateral projections (Fig. 51D); phallus with loop forming acute angle (Fig. 51C); hind tarsomere 1 swollen, wider than hind tibial width at apex (Fig. 51B)................................ R. herschelli Malloch

- Sternite 8 without projections; phallus with small in-ward U-shaped loop (Fig. 57A); hind tarsomere 1 slender (Fig. 56B)........................................................................................ R. laevigata Loew

20 Midleg distinctly modified: femur strongly curved upwards; tibia curved inwards, with 3–5 dark, stout mid-posterodorsal setae longer than 2X tibial width; tarsomere 1 spindle-shaped, covered with dense, erect and moderately long setae (Figs 42A, B)................................................ R. (P.) petervajdai Sinclair, Vajda, Saigusa & Shamshev sp. nov.

- Midleg simple....................................................................................... 21

21 Apex of epandrium truncate (Figs 44A, C); hind tibia with distinctive inward bend on apical part; hind tarsomere 1 spindleshaped, convex dorsally but straight ventrally (Fig. 44B)................................................................................................... R. (P.) septentrionalis Sinclair, Vajda, Saigusa & Shamshev sp. nov.

- Apex of epandrium rounded; hind tibia straight; hind tarsomere 1 clavate or uniformly slender....................... 22

22 Anepisternum shiny and scutum with 1–2 pairs of shiny vittae; hind tarsomere 1 clavate, increasing in size apically such that apical width broader than hind tibia (Fig. 48B); cerci weakly constricted in middle, posterior half parallel to epandrium (Fig. 48A).......................................................................... R. (P.) ursinella Melander

- Anepisternum pruinose and scutum with pruinescent vittae; hind tarsomere 1 evenly slender, nearly as broad as apical width of hind tibia, (Fig. 25B); cerci strongly constricted in middle, posterior half strongly divergent from epandrium (Fig. 25A)....................................................................... R. (P.) filicauda Henriksen & Lundbeck