Key to known species of Soita Walker

1. Scutellum with 2 pairs of setae (Figs. 120, 124); anepisternum and katepisternum anteroventrally with longitudinal row of short black spines along margin.......................................................................... 2

- Scutellum with 1 pair of setae (Figs. 131, 140, 145); anepisternum without short black spines along anteroventral margin... 3

2. Scutum uniformly yellow to yellow-brown; wing with cell Sc brown, lacking slight infuscation at apices of vein Cu l and Dm- Cu (Fig. 123) (Luzon, Philippines)........................................................... S. ensifera Hardy

- Scutum yellow-brown with 2 pairs of narrow, pale yellow stripes; wing hyaline but slightly tinged with brown, cell Sc with apical half brown, and a distinct brown mark covering apex of vein Cu l and Dm-Cu (Fig. 119) (Indonesia, China and Japan)..................................................................................... S. cylindrica (Hendel)

3. Katepisternum anteroventrally with 3 marginal longitudinal rows of short brown spines; all body setae yellow to brown except for 1 pair strong orbital seta dark brown (Equatorial Guinea, Uganda)................. S. ophioneum (Enderlein) n. comb

- Katepisternum lacking spines; body setae not as above........................................................ 4

4. Head with 1 distinct long-oval black spot at base of orbital seta on each side and 1 irregular black spot on median occipital sclerite (Fig. 110); abdomen yellow to yellow-brown, but with black posterior bands on syntergite 1+2 and tergites 3–5 (Bohol, Philippines)........................................................................... S. baltazarae Hardy

- Head without brown orbital and occipital marks; abdomen lacking black posterior bands on syntergite 1+2 and tergites 3–5...................................................................................................... 5

5. Wing with apices of radial cells infuscated (Fig. 128); abdominal tergites 3 and 4 with pair of outstanding submedial posterior setae; head yellow, with distinct narrow medial brown stripe on frons (New Caledonia)....................................................................................................... S. infuscata Chen & Norrbom, n. sp.

- Wing with apices of radial cells not infuscated (Fig. 144); abdominal tergites 3 and 4 lacking pair of outstanding submedial posterior seta; head yellow to brown, without dark marks except ocellar tubercle or with vague medial brown stripe on frons (Indonesia, Papua New Guinea, Australia)................................................... S. psiloides Walker