A world key to the species of the genus Robackia Saether (male)

(adopted from Yan et Wang 2006)

1. Anal point without any lateral setae, only with basal strong setae (Holarctic: United States, Canada, China)......................................................................................... R. demeijerei (Kruseman, 1933)

- Anal point with weak lateral setae, with or without basal strong setae............................................ 2

2(1). Tergite IX with shoulders............................................................................... 3

- Tergite IX with posterior margin rounded................................................................... 4

3(2). Superior volsella swollen distally; anal point nearly parallel–sided (Palaearctic and Orient: former Yugoslavia, Italy, North Korea, Russia, China).............................................................. R. pilicauda Saether, 1977

- Superior volsella not swollen distally; anal point widened in apical 1/3 (Palaearctic: Russia)....... R. aculeata Zorina, 2003

4(2). Anal point constricted basally (Nearctic: United States).................................. R. claviger (Townes, 1945)

- Anal point nearly parallel-sided.......................................................................... 5

5(4). AR 1.30; T IX with 4 strong dorsal setae; superior volsella digitiform with 1 subapical and 1 apical setae (Oriental China)............................................................................. R. parallela Yan et Wang, 2006

- AR 2.03–2.13; T IX without strong setae; superior volsella bilobed, inner part with 1 subapical and 1 apical setae (Orient: India)............................................................................... R. aequilongia sp. n.