Key to Anthroleucosomatidae species in the Caucasus

1. Adults with 28 or 30 segments, including telson.............................................................2

- Adults with 29 or 31 segments, including telson............................................................24

2. Male posterior gonopods with well-developed and somewhat robust telopodites (Figs 5 D, 9D)........................3

- Male posterior gonopods with small, poorly-developed telopodites (Figs 14 D, 17D, 20D, 41D, 44G, 55D, 60H ect)........ 5

3. Coxal process of male leg-pair 7 with very short and thick setae. Midbody walking legs with enlarged and somewhat elongated coxae..................................................................... Alloiopus solitarius Attems, 1951

- Coxal process of male leg-pair 7, if present, without characteristic setae. Midbody walking legs with normal coxae...................................................................................... Golovatchosoma gen. nov. ...4

4. Male leg-pair 7 with a posterior coxal horn (Fig. 4 C). Macrochaetae of body segments short and bacilliform (Figs 2 B, 3).............................................................................. G. bacillichaetum gen. et sp. nov.

- Male leg-pair 7 without posterior coxal horn. Macrochaetae of body segments medium-sized and trichoid (Fig. 7).................................................................................... G. trichochaetum gen. et sp. nov.

5. Coxites of posterior gonopods with a single coxal process (Figs 14 D; 17D; 55D; 81D; 82D, E, F; 85D; 86D, E, F; 89D; 90F, G, H)..................................................................................................6

- Coxites of posterior gonopods with paired coxal processes (Figs 20 D; 23D; 27D; 37D; 41D; 59D; 64D; 68D; 72D; 77D; 165G, H).................................................................................................11

6. Posterior margins of pleurotergites without limbus...........................................................7

- Posterior margins of pleurotergites with a denticulate limbus (Figs 80 D; 84D, 88D)............ Dentatosoma gen. nov. ... 9

7. Anterior gonopods with a medial syncoxal structure and lateral parts; without anterior sternal sac (Fig. 14 A)........................................................................................ Alpinella waltheri gen. et sp. nov.

- Anterior gonopods in the form of shields; with an anterior sternal sac (Figs 17 A; 55A)...............................8

8. Prefemur of male leg-pair 7 with two distinctive, well-developed, apical and basal horns (Fig. 16 C). Anterior gonopods with a medial, unpaired, bifurcated process (Fig. 17 A)......................... .. Brachychaetosoma turbanovi gen. et sp. nov.

- Prefemur of male leg-pair 7 without any special structures. Anterior gonopods in the form of rounded shields, without medial bifurcated process; each shield with one distinctive, subtriangular and acuminate horn in anterior view (Fig. 55 A)............................................................................. Georgiosoma bicornutum gen. et sp. nov.

9. Coxal processes of anterior gonopods narrow (Figs 81 A; 82A; 89A; 90A)........................................10

- Coxal processes of anterior gonopods expanded in the middle (Fig. 85 A).................... D. magnum gen. et sp. nov.

10. Coxal processes of anterior gonopods ending with a few denticles (Figs 81 B; 82A)....... .. D. denticulatum gen. et sp. nov.

- Coxal processes of anterior gonopods ending with a long, laterally and downward orientated horn (Figs 89 A; 90B)...................................................................................... D. zeraboseli gen. et sp. nov.

11. Anterior gonopods with robust anterior sternal processes fused in distal ¾ (Fig. 165 A). Body length ± 6 mm .................................................................................. Uegrandosoma tabacarui gen. et sp. nov.

- Anterior gonopods without robust anterior sternal processes. Body length Ż 8 mm .................................12

12. Coxites of posterior gonopods with a pair of flagelliform processes (eg Fig. 27 D)..................................13

- Coxal processes of posterior gonopods not flagelliform, but shorter and thicker (Figs 68 D; 72D; 77D)................................................................................................. Paranotosoma gen. nov. ...22

13. Anterior gonopods with shield-like coxal processes (eg Fig. 27 A)....................... Caucaseuma Strasser, 1970, 14

- Anterior gonopods with an unpaired medial part and two lateral processes (Figs 59 A; 64A; 65A)................................................................................................. Heterocaucaseuma gen. nov. ...20

14. Adults with 28 segments, including telson................................................... C. variabile sp. nov.

- Adults with 30 segments, including telson................................................................. 15

15. Anterior gonopods with two distinctive, bifurcated, posterior projections/processes (Fig. 20 B, C)... .. C. elephantum sp. nov.

- Anterior gonopods without such a posterior projection.......................................................16

16. Posterior coxal processes of anterior gonopods starting with an anterior horn (Figs 23 C; 27C; 31B)....................17

- Posterior coxal processes of anterior gonopods starting with a lamella (Fig. 37 B).................... C. minellii sp. nov.

17. Both anterior shields of the anterior gonopods divided distally into a medial and a lateral part (Figs 31 A; 34A).......... 18

- Anterior shields of anterior gonopods unipartite (Figs 23 A; 27A)............................................... 19

18. Prefemur of male leg-pair 7 with a mesal dentate bulge in basal half....................... C. lohmanderi Strasser, 1970

- Prefemur of male leg-pair 7 without any peculiarities......................................... .. C. kelasuri sp. nov.

19. Coxae of male leg-pair 7 with a small, posterior, dentate, subtriangular process (Fig. 22 D)...... .. C. fanagoriyskaya sp. nov.

- Male leg-pair 7 without peculiarities................................................... C. glabroscutum sp. nov.

20. Lateral horns and medial part of anterior gonopods almost equally high (Figs 59 A; 60A)..................................................................................................... H. feminaepectorum gen. et sp. nov.

- Lateral horns clearly higher than medial part (Figs 64 A; 65A).................................................21

21. Medial part acuminate in anterior view (Fig. 64 A). Lateral horns with lateral shoulders....... H. longicorne gen. et sp. nov.

- Medial part squarish in anterior view. Lateral horns without lateral shoulders.. .. H. mauriesi (Golovatch and Makarov, 2011)

22. Anterior coxal shields squarish or nearly rounded (Figs 68 A; 77A; 78A). Posterior coxal processes with an additional lateral process (Figs 68 B, C; 77B, C; 78C, D, E)................................................................. 23

- Anterior coxal shields cordiform (Figs 72 A, 73A). Posterior coxal processes without an additional lateral process (Fig. 72 B, C)............................................................................... P. cordatum gen. et sp. nov.

23. Shields nearly rounded (Figs 77 A; 78A). Lateral process club-like (Figs 77 B; 78C). Coxae of male leg-pair 7 with two short processes (Fig. 76 C)......................................................... P. subrotundatum gen. et sp. nov.

- Shields squarish (Fig. 68 A). Lateral process long and slender (Fig. 68 B, C). Coxae of male leg-pair 7 with only one rudimen- tary coxal process (Fig. 67B)....................................................... .. P. attemsi gen. et sp. nov.

24. Anterior gonopods anteriorly with a pair of flagella/pseudoflagella or thorn-like processes (Figs 120 A; 124A; 125A; 128A; 133A; 137A; 142A; 146A; 150A; 151A)..................................................................25

- Anterior gonopods without such structures.................................................................32

25. Anterior gonopods anteriorly with a pair of hidden processes, with only distal third visible (Fig. 133 A–D)........ Cryptacan- thophorella manubriata gen. et sp. nov.

- Anterior gonopods anteriorly with a fully visible pair of flagella/pseudoflagella or thorn-like processes (eg Figs 120 A; 137A; 146A)..............................................................................................26

26. Body with 29 segments in adults (including telson). Anterior gonopods anteriorly with a pair of flagella protected by a well- developed anterior sternal lamella (Fig. 138 A).............................. Flagellophorella hoffmani gen. et sp. nov.

- Body with 31 segments in adults (including telson). Anterior gonopods anteriorly with a pair of pseudoflagella or thorn-like processes, without protective lamella (eg Figs 120 A; 146A)...................................................27

27. Anterior gonopods anteriorly with a pair of thorn-like processes (Figs 120 A; 124A; 128A). Sternal plate with a small sternal sac......................................................................... Acanthophorella gen. nov. ...28

- Anterior gonopods anteriorly with long and slender processes in the form of pseudoflagella (Figs 142 A; 146A; 150A). Sternal plate with a sternal lamella................................................. Pseudoflagellophorella gen. nov., 30

28. Body length 16–18 mm, pigmentless. Head 5–7 ocelli. Walking legs and antennae elongated. Cavernicolous species (Fig. 118).............................................................................. A. barjadzei gen. et sp. nov.

- Body length ± 10.5 mm, pigmented. Head with 13–17 ocelli. Walking legs and antennae normal. Epigean species (Figs 121; 126)................................................................................................29

29. Lateral lamella of anterior gonopods higher than thorn-like processes (Fig. 124 A). Coxal processes of posterior gonopods well-developed (Fig. 124 D)....................................................... .. A. chegemi gen. et sp. nov.

- Lateral lamella of anterior gonopods denticulate and lower than thorn-like processes (Fig. 128 A). Coxal processes of posterior gonopods small (Fig. 128 D).......................................................... A. irystoni gen. et sp. nov.

30. Basal parts of anterior gonopods very wide and rounded (Fig. 142 A).......................... P. eskovi gen. et sp. nov.

- Basal parts of anterior gonopods not rounded; almost same in width as remaining parts of gonopods...................31

31. Anterior gonopods with fimbriated lateral parts showing numerous single, bi- or three-ramous fringes/fingers orientated poste- riorly (Fig. 146 A)................................................................ P. mirabilis gen. et sp. nov.

- Anterior gonopods in the form of butterfly wings; with neither fimbriated lateral parts nor fringes/fingers (Fig. 150 A).................................................................................. P. papilioformis gen. et sp. nov.

32. Posterior gonopods without traces of telopodites................................ Ratcheuma excorne Golovatch, 1985

- Posterior gonopods with telopodites......................................................................33

33. Anterior gonopods divided into at least two or more lateral branches (Figs 94 A; 98A; 103A; 108A; 112A; 116A)......... 3 4

- Anterior gonopods unipartite............................................................................39

34. Anterior gonopods with a medial part and four pairs of processes (Fig. 94 A)........... Enghoffiella insolita gen. et sp. nov.

- Anterior gonopods with a medial part and two lateral branches, inner and outer (98A; 103A; 108A; 112A; 116A)............................................................................ Metamastigophorophyllon Ceuca, 1976, 35

35. Anterior gonopods with a poorly-developed, hairless, sternal lamella (Figs 98 A; 99A)........... M. giljarovi (Lang, 1959)

- Anterior gonopods with a well-developed, mainly densely setose, sternal lamella (Figs 103 A; 108A; 112A; 116A)........3 6

36. Inner branch of anterior gonopods with a characteristic hook-shaped process (Figs 103 A; 104C–D)... ... M. hamatum sp. nov.

- Inner branch of anterior gonopods without a hook-shaped process..............................................37

37. Outer branch of lateral part of anterior gonopods fimbriated and with numerous simple, bi- or triramous fringes/fingers (Figs 116 A, C; 117B–D)..................................................................... M. torsivum sp. nov.

- Outer branch not fimbriated............................................................................ 38

38. Sternal plate with a stongly developed, hairy, sternal lamella with a raised, medial, bifurcated part (Figs 108 A; 109A). Outer branches strongly developed, wide, lamellar (Figs 108 A; 109A). Male leg-pair 7 with a coxal cavity, prefemur with a poster- omesal acuminate process (Fig. 107 D)............................................... M. lamellohirsutum sp. nov.

- Sternal lamella not as above. Outer branches narrower, not in the form of a lamella. Male leg-pair 7 with neither a coxal cavity nor a prefemoral acuminate process................................................. M. martensi (Mauriès, 1982)

39. Male leg-pair 6 particularly robust and bizarre (Figs 154 C; 158C). Coxites of posterior gonopods with numerous arrow-shaped filaments (Figs 155 D; 159D).......................................................... Herculina gen. nov. ...40

- Male leg-pair 6 not as above. Coxites of posterior gonopods without arrow-shaped filaments......................... 41

40. Arrow-shaped filaments on coxites of posterior gonopods more numerous, with an isolated long filament (Fig. 159 D)................................................................................... H. polysagittae gen. et sp. nov.

- Arrow-shaped filaments on coxites of posterior gonopods significantly less numerous, an isolated filament absent (Fig. 155 D).......................................................................... .. H. oligosagittae gen. et sp. nov.

41. Head in males with a medial frontal tubercle between antennal sockets and with a depression between both ocellaria (Fig. 10 B, C).................................................................... Adshardicus strasseri Golovatch, 1981

- Head in males normal......................................................... Caucasominorus gen. nov. ....42

42. Shields of anterior gonopods with numerous striae (Figs 46 A; 47A). Coxal processes of posterior gonopods with one or two knife-like lobes (Fig. 46 E)............................................................ C. billi gen. et sp. nov.

- Shields of anterior gonopods almost completely smooth (Figs 51 A; 52A). Coxal processes of posterior gonopods with more numerous knife-like lobes (Figs 49 E, F; 51D)....................................... C. polylobatus gen. et sp. nov.