Key to Palaearctic Zodion species with a uniformly dusted abdomen and lacking any blackish spots at

the bases of the hairs on either the thorax, abdomen or, where they are present, the scutellum. Cell r4+5 is usually open, although this is variable. (Species marked with an * are not known to me but are included in the key using characters from their original descriptions)

1 Scutellum only has black bristles on the posterior margin, lacking any additional hairs on the dorsal surface (fig. 16); scutum with only one pair of indistinct stripes; frons with only a few long hairs at the base (fig. 13); radial cell r4+5 closed (fig. 15), vein R4+5+M may be developed; shape of surstylus as fig. 18, with a broad base; posterior surstylus with a small inconspicuous dorsal membranous appendage (fig. 18: mpsu).................................................... hauseri spec. nov.

- Scutellum with numerous black hairs dorsally, in addition to black bristles on the posterior margin; scutum usually with at least two distinct pairs of stripes; frons completely covered with long black hairs (except in pamirensis); radial cell r4+5 open (individual exceptions occur), vein R4+5+M not developed; shape of surstyli (of the known species) different, without a broad base and with a large membranous appendage.................................................................... 2

2 Antenna completely black............................................................ nigricorne Chen, 1939 *

- Antenna always at least partly brown or orange-brown........................................................ 3

3 Pedicel obviously longer than basal flagellomere; legs, including coxae, mainly light orange-brown; surstyli as figured by Mei & Stuke (2008: 9, fig. 11) ........................................... kroeberi Szilády, 1926, rufipes Chen, 1939 *

- Pedicel may be about as long as basal flagellomere but not longer; legs mainly grey, tarsi blackish..................... 4

4 Antenna brown and partly black; frons entirely covered with long hairs (fig. 2); scutum without medial stripe; no stripe reaching from the postpronotum to the scutellum (fig. 3); abdomen golden (♂) or silver (♀) dusted; several hairs on abdomen longer than arista; shape of surstylus as fig. 5, posterior surstylus with a large lateral membranous appendage (fig. 6: mpsu)........

.............................................................. andersoni Kröber, 1936, pilosum Chen, 1939 * - Antenna completely orange; frons almost completely lacking long hairs; scutum with a medial stripe, and additionally with two pairs of submedial and sublateral stripes, the sublateral stripes reaching from the postpronotum to the scutellum; abdomen dusted silky yellow; hairs on abdomen shorter than the arista; shape of surstylus unknown........ pamirense Zimina, 1974 *