Key to the species of Caucasian Leugogeorgiini

1. Mouthparts normal...........................................................................................................................2 – Mouthparts modified.........................................................................................................................9

2. Head with ommatidia; metazonal setae absent (Figs 29–31) ............. Leucogeorgia oculata sp. nov. – Head without ommatidia; metazonal setae present...........................................................................3

3. Mesomeral claw (mc) with teeth.........................................................................................................4 – Mesomeral claw (mc) without teeth....................................................................................................7

4. Mesomeral claw (mc) stocky and robust (Figs 16–18) .................. Leucogeorgia borealis sp. nov. – Mesomeral claw (mc) more slender.................................................................................................5

5. Mesomeral claw (mc) with poorly developed teeth (almost absent); mesomeral lamella (ml) strongly serrate distally (Figs 19–21) ....................................................... Leucogeorgia gioi sp. nov.

– Mesomeral claw (mc) with well-developed teeth; mesomeral lamella (ml) not strongly serrated distally................................................................................................................................................6

6. Mesomeral lamella (ml) sloping down posteriad, without posterior rise; midbody setae ca 5% of vertical diameter of rings (Figs 3–6) ......... Leucogeorgia abchasica (Lohmander, 1936) comb. nov.

– Mesomeral lamella (ml) flattened, with a posterior rise; midbody setae ca 10% of vertical diameter of rings (Figs 14–15) ................................... Leucogeorgia satunini (Lohmander, 1936) comb. nov.

7. Body ring 2 in both sexes with well-developed ventral lobes (Figs 22–24) ................................. ....................................................................................................... Leucogeorgia golovatchi sp. nov. – Body ring 2 without lobes...............................................................................................................8

8. Mesomeral lamella (ml) with a strongly developed lobe (l) (Figs 25–26, 27 A–C, 28) ................ ............................................................................................................. Leucogeorgia lobata sp. nov.

– Mesomeral lamella (ml) without such a strongly developed lobe (l); if ml present, then poorly developed (Figs 32–35) .............................................................. Leucogeorgia prometheus sp. nov.

9. Mesomeral lamella (ml) reduced, connected to base of mesomere (Figs 50–51) .......................... .......................................................................................................... Martvilia parva gen. et sp. nov. – Mesomeral lamella (ml) strongly developed, starting just below mesomeral claw (mc)......10

10. Mesomeral claw (mc) without teeth (Figs 7–10) .............. Leucogeorgia longipes Verhoeff, 1930 – Mesomeral claw (mc) with teeth...................................................................................................11

11. Labrum strongly divided into two lobes; gnathochilarium with a distolateral bundle of long setae on stipites; lamellae linguales with two irregular rows of long, distal setae (Figs 39–41) .... ............................................................................................................. Leucogeorgia mystax sp. nov.

– Labrum only slightly concave in middle; gnathochilarium without such groups of setae.........12

12. Posterior margin of hypoproct with a characteristic rounded extension in both sexes (Figs 42–43) .......................................................................................................... Leucogeorgia profunda sp. nov. – Posterior margin of hypoproct without rounded extension.............................................................13

13. Epiproct with very long and sharp process, apically with a hyaline tip slightly curved upwards (Figs 36–38) ....................................................................................... Leucogeorgia caudata sp. nov. – Epiproct with a short or not too long and sharp process, without hyaline tip...........................14

14. Anal valvae densely setose (Figs 47–49) .................................... Leucogeorgia turbanovi sp. nov. – Anal valvae setose, but not too densely so..................................................................................15

15. Body elongate, with 38–47 podous rings in males; hypoproct lanceolate; ventral margin of body ring 7 rounded; mesomeral lamella (ml) with a rather smooth, high and lobe-shaped central part (Figs 11–13) .......................................................................... Leucogeorgia rediviva Golovatch, 1983

– Body stocky, with 28–35 podous rings in males; hypoproct subrhomboid; ventral margin of body ring 7 low, more subquadrangular; mesomeral lamella flattened, slightly denticulate in central part (Figs 44–46) .......................................................... Leucogeorgia redivivoides sp. nov.