Genus Vanhornia Crawford, 1909

Vanhornia Crawford, 1909: 63 . Type species: Vanhornia eucnemidarum Crawford, 1909 by original designation. Sincivanhornia He & Chu, 1990: 102 (synonymized by Kozlov (1998)).

Key to world species of Vanhornia .

1 Longitudinal ridges on syntergite long, reaching to 0.7–0.8 length of syntergite (Figs. 4E, F)........ V. leileri Hedqvist, 1976

- Longitudinal ridges on syntergite short, reaching to a maximum of 0.4 length of syntergite (Fig. 1F)................... 2

2 Frontal transverse carina present (Fig. 2B). Mesodiscrimen with approximately six strong foveae (Fig. 6E). Longitudinal ridges on syntergite not touching first thyridium (Fig. 2F)........................................................... 3

- Frontal transverse carina absent (Figs. 3B and 7B). Mesodiscrimen with about 10 strong foveae (Fig. 1D). Longitudinal ridges on syntergite touching first thyridium (Figs. 1F and 3F)....................................................... 4

3 Punctures between median ocellus and frontal transverse carina large, larger than punctures on anterior half of head (Fig. 2C). Scutoscutellar sulcus with six foveae (Fig. 2D). Transverse carina on propodeum incomplete (Fig. 2E).. V. formosana sp. nov.

- Punctures between median ocellus and frontal transverse carina small, same size with punctures on anterior half of head (Fig. 6C). Scutoscutellar sulcus with five foveae (Fig. 6D). Transverse carina of propodeum complete (Fig. 6F)......................................................................................... V. quizhouensis (He & Chu, 1990)

4 Scutoscutellar sulcus with seven foveae (Fig. 7E)............................ V. yurii Timokhov & Belokobylskij, 2020

- Scutoscutellar sulcus with five foveae (Fig. 1C)............................................................. 5

5 Apical margin of labrum straight (Fig. 1B). Median longitudinal carina on dorsal part of propodeum present (Fig. 1E). Antero-dorsal margin of syntergite almost straight (Fig. 1F). Nearctic (Canada and USA).. V. eucnemidarum Crawford, 1909

- Apical margin of labrum weakly convex (Fig. 3C). Median longitudinal carina on dorsal part of propodeum absent (Fig. 3E). Antero-dorsal margin of syntergite concave (Fig. 3F). East Palaearctic (Japan)................... V. hikosanensis sp. nov.