Key to subgenera of Leptochilus

1 Tergum 2 without apical lamella, its posterior margin either straight or bent upwards; New World species......... Zendalia

- Tergum 2 with apical lamella, which is either straight or bent upwards; Old World species............................ 2

2 Body size more than 12 mm; setae on scutum longer than scapus width (one species, L. mauritanicus)..... Leptochilus s. str.

- Body size less than 10 mm; setae on scutum usually shorter than scapus width..................................... 3

3 Tegula big, more than half of scutellum area...................................................... Euleptochilus

- Tegula smaller, less than half of scutellum area.............................................................. 4

4 Labial palpi with at least 20–30 long setae (not shorter than scapus width) each; palpomere 1 nearly as long as total length of palpomeres 2–4................................................................................ Sarochilus

- Labial palpi with maximum 2–3 long setae each, as well as with numerous minute setae; palpomere 1 distinctly longer than total length of palpomeres 2–4............................................................................... 5

5 Apical lamella of tergum 2 weakly sclerotized, semitransparent, with basal row of punctures in the form of either dots or longitudinal dashes............................................................................... Lionotulus

- Apical lamella of tergum 2 strongly sclerotized, nontransparent, with basal row of punctures always in the form of longitudinal dashes................................................................................... Neoleptochilus