Key to Old World species of Pseudognaptodon Fischer

1. Pterostigma slender and vein r emitted distinctly before middle of pterostigma (Fig. 33 in Belokobylskij 1992); vein 3-SR+SR1 of fore wing nearly straight; first tergite subparallel-sided posteriorly; first and second tergites largely longitudinally striate; 4 (♂)–5 (♀) basal antennal segments yellow; mesosoma light brown dorsally; [basal area of second tergite 0.1 × as long as com- bined second and third tergites and smooth; eye in dorsal view 1.8–2.2 × as long as temple; first and second metasomal tergites yellow dorsally; second metasomal suture smooth (Fig. 32 l. c.)]....................... P. ruficeps Belokobylskij, 1993

- Pterostigma robust and vein r usually emitted near middle of pterostigma or slightly before middle (Figs 2, 14, 25, 37); vein 3- SR+SR1 of fore wing distinctly curved, at least basally so (Figs 2, 14, 25, 37); first tergite gradually widened posteriorly (Figs 5, 40); first and second tergites largely smooth, rugulose or rugose (Figs 5, 18, 29, 40); either only scapus yellow (Fig. 45), or 4 basal antennal segments yellowish (Figs 10, 22) and mesosoma dorsally largely or entirely black or dark brown (Figs 4, 17) ................................................................................................... 2

2. Vein 1-R1 1.2–1.5 × longer than pterostigma (Figs 2, 14); frons granulate (Figs 8, 20); episternal scrobe present, linear (Figs 1, 12); vein 2-M of fore wing at least as long as vein 2-SR (Figs 2, 14); face yellowish brown; basal area of second metasomal tergite smooth (Figs 5, 16); Oriental (Vietnam).............................................................. 3

- Vein 1-R1 0.8–1.0 × as long as pterostigma (Figs 25, 37); frons rugulose or aciculate (Figs 32, 43); episternal scrobe absent (Figs 24, 36); vein 2-M of fore wing at least slightly shorter than vein 2-SR (Fig. 25); face dark brown or yellowish (Figs 31, 42), if yellowish then basal area of second tergite sculptured (Fig. 40)............................................ 4

3 Vein 3-SR+SR1 of fore wing evenly curved (Fig. 14); two basal metasomal tergites brownish yellow (Fig. 18); occiput medially and mesopleuron yellowish brown (Figs 15, 20)................................ P. curvinervis van Achterberg, sp. n.

- Vein 3-SR+SR1 of fore wing only basally distinctly curved (Fig. 2); two basal metasomal tergites black (Fig. 5); occiput dark brown medially (Fig. 8) and mesopleuron black (Fig. 3)......................... P. bidoupensis van Achterberg, sp. n.

4 Basal area of second tergite rugose-punctate and 0.10 × as long as combined second and third tergites (Fig. 40); vein 3-SR+SR1 of fore wing distinctly curved basally (Fig. 37); eye in dorsal view approx. 9.5 × as long as temple, temple directly narrowed posteriorly (Fig. 43); first and second metasomal tergites black dorsally; second metasomal suture obsolescent medially (Fig. 40); scutellar sulcus distinctly crenulate (Fig. 39); vertex aciculate (Fig. 43); antenna with approx. 30 segments; length of body approx. 2.6 mm; Palaearctic (China)..................................... P. sinensis Tan & van Achterberg, sp. n.

- Basal area of second tergite smooth and 0.15 × as long as combined second and third tergites (Fig. 29); vein 3-SR+SR1 of fore wing entirely evenly curved (Fig. 25); eye in dorsal view approx. 3.5 × as long as temple, temple gradually narrowed posteriorly (Fig. 32); second metasomal suture distinctly impressed medially (Fig. 29); scutellar sulcus almost smooth (Fig. 28); vertex rugulose (Fig. 32); antenna with approx. 19 segments; length of body approx. 1.5 mm; [vein 1-R1 slightly shorter than pterostigma]; Oriental (Vietnam)................................................. P. longi van Achterberg, sp. n.