Key to world species of genus Macgregoromyia

Except for the new species, the key was compiled based on the literature as indicated. For brevicula, celestia, shikokuana and szechwanensis include reference to the very detailed figures in Savchenko 1983 (wing and male genitalia). For fohkienensis includes a female specimen from Chinese province Zhejiang.

1. Distal cells of wing with macrotrichia..................................................................... 2

- Distal cells of wing bare................................................................................ 4

2. Wing with r-m strongly arcuated, entering R4+5, R4+5 basally bent basad (Alexander, 1955, p 367, fig. 2)................................................................................................. M. syusiro Alexander, 1955

- Wing with r-m slightly arcuated, entering Rs, R4+5 straight basally............................................... 3

3. Wing with R1+2 absent; posterior margin of tergite 9 with a V-shaped incision; apex of lobe of gonostylus narrowed; dorsal crest of clasper of gonostylus greatly convex (Alexander 1932, Pl. I, fig. 3, Pl. II, fig. 32)..... M. szechwanensis Alexander, 1932

- Wing with R1+2 entire (Fig. 5); tergite 9 (Fig. 17) with posterior margin bearing three processes; lobe of gonostylus (Fig. 18) with tip broad; clasper of gonostylus (Fig. 19) with dorsal crest smooth........................ M. ternifoliusa sp. nov.

4. Wing with r-m entering Rs at fork of Rs.................................................................... 5

- Wing with r-m either entering Rs before fork of Rs or entering R4+5 beyond fork of Rs............................... 6

5. Femora brown with tips blackened; posterior margin of tergite 9 narrowly emarginated; basal beak of clasper of gonostylus short and obtuse, dorsal crest of clasper of gonostylus with a spine-like process, posterior crest laterally with a collar-like flange (Alexander 1969, p 34, figs. 1, 2)............................................. M. babana Alexander, 1969

- Femora dark brown with bases broadly more yellowed; median lobe of tergite 9 very reduced; basal beak of clasper of gonos- tylus long and pointed, dorsal crest of clasper of gonostylus smooth, posterior crest small, without such flange (Alexander 1954, Pl. I, figs. 1, 8).......................................................... M. shikokuana Alexander, 1954

6. Wing with r-m entering R4+5 beyond fork of Rs.............................................................. 7

- Wing with r-m entering Rs before fork of Rs................................................................ 8

7. Tergite 9 medially notched; posterior crest of clasper of gonostylus produced into an obtuse lobe (Alexander 1933, Pl. II, fig. 26).......................................................................... M. brevicula Alexander, 1933

- Tergite 9 medially produced into a semicircular blade; posterior crest of clasper of gonostylus convex with apex produced backwards (Alexander 1955, p 365)..................................................... M. itoi Alexander, 1955

8. R1+2 entire............................................................................................ 9

- R1+2 spur-like or absent................................................................................ 12

9. Rs original long before line of r-m (Alexander 1929, Pl. I, fig. 3)..................... M. benguetensis Alexander, 1929

- Rs original nearly in line with r-m....................................................................... 10

10. CuA1 meeting M3 near middle of cell dm (Edwards 1932, p 54)...................... M. perpendicularis Edwards, 1932

- CuA1 meeting M3 near fork of M........................................................................ 11

11. CuA1 meeting M3 at a point (Fig. 10); tergite 9 with posterior margin bearing a shallow U-shaped incision (Fig. 21); dorsal crest of clasper of gonostylus flat (Fig. 23)................................................... M. flatusa sp. nov.

- CuA1 fused with M3 for a short distance; tergite 9 with posterior margin bearing a deep U-shaped notch; dorsal crest of clasper of gonostylus convex (Alexander 1931, Pl. I, fig. 5, Pl. III, figs. 44–46)................. M. brevisector Alexander, 1931

12. First flagellomere black or brown with base yellow.......................................................... 13

- First flagellomere entirely yellow....................................................................... 14

13. Rs arcuated before joint with r-m; R1+2 spur-like, apex touching Sc2 and closing cell sc2 (Fig. 15)................................................................................................... M. fohkienensis Alexander, 1949

- Rs straight before joint with r-m; R1+2 represented by a basal spur, paralleled with Sc2 (Fig. 14).... M. rectangularis sp. nov.

14. r-m meeting Rs near fork of Rs; beak of clasper of gonostylus produced (Alexander 1962, Pl. I, fig. 1, Pl. III, fig. 39).................................................................................. M. sikkimensis Alexander, 1962

- r-m meeting Rs nearly at middle of Rs; beak of clasper of gonostylus small and bent downwards (Alexander 1932, Pl. I, fig. 4, Pl. II, fig. 34).................................................................. M. celestia Alexander, 1932