Chthonius heterodactylus group, 1843

Gardini, Giulio, 2014, The species of the Chthonius heterodactylus group (Arachnida, Pseudoscorpiones, Chthoniidae) from the eastern Alps and the Carpathians, Zootaxa 3887 (2), pp. 101-137 : 103

Key to adults of species of the Chthonius heterodactylus group from the eastern Alps and the Carpathians

1. Epigean or endogean eyed species, rarely with slightly troglomorphic facies; carapace with 18 macrosetae: anterior row with or without preocular microsetae, ocular row with 6 macrosetae ( Figs 4–5 , 14 , 83 ); tergites I–II with 4 setae each; movable chelal finger with 16–38 reclined ( Figs 23–26 , 80–81 ) or partially erect teeth ( Figs 9–11 ); chela 4.8–6.9 (♂) or 4.3–5.9 (♀) times as long as deep, ratio of pedipalpal femur/carapace 1.15–1.98 (♂♀)........................................ 2

- Hypogean anophthalmic species with strongly troglomorphic facies; carapace with 16 macrosetae: chaetotaxy 4:m 4m:4:2:2(18), rarely m 4m:4:4:2:2(18), lateral microsetae with variable position from ocular to anterior row; ocular row with 4 macrosetae ( Fig. 44 ); tergites I–II with 2 setae each; movable chelal finger with 35–54 contiguous, reclined triangular teeth ( Figs 48–49 ); pedipalps usually more slender: chela 6.6–7.6 (♂) or 6.1–7.3 (♀) times as long as deep, ratio of pedipalpal femur/carapace 1.75–2.15 (♂♀)................................................. C. lessiniensis Schawaller, 1982

2. Fixed chelal finger with distal paraxial seta gradually acuminate and curved, not thickened or only weakly so ( Figs 18–19 , 24–26 , 56–58 ); carapace with ( Figs 12–13 , 20 ) or without ( Figs 50–52 ) epistome and with 1 or 2 lateral microsetae on each side of anterior row and usually 1 lateral microseta on each side of posterior row; fixed chelal finger usually without intercalary microdenticles ( Figs 23–26 , 56–58 ).................................................................. 3

- Fixed chelal finger with distal paraxial seta spatulate, thickened in the middle ( Figs 9–10 , 80–81 ); carapace without epistome ( Figs 1–3 , 75–76 ) and usually without lateral microsetae on anterior and posterior rows; fixed chelal finger usually with intercalary microdenticles ( Figs 9–10 , 86–87 )................................................................. 5

3. Carapace with epistome ( Figs 12–13 , 20 ) and with two lateral microsetae on each side in anterior row ( Figs 14 , 21 ); fixed and movable chelal fingers respectively with 18–50 and 18–38 teeth; fixed chelal finger with distal paraxial seta gradually sharp and curved, not enlarged ( Figs 18–19 , 24–26 ); coupled sensilla pc of movable chelal finger usually between trichobothria st and sb; species from Carpathians........................................................................ 4

- Carapace without epistome ( Figs 50–52 ) and with 1 lateral microseta on each side on anterior row ( Fig. 53 ); fixed and movable chelal fingers respectively with 16–22 and 18 teeth; fixed chelal finger with distal paraxial seta sinuous and weakly enlarged ( Figs 56–58 ); coupled sensilla pc of movable chelal finger between trichobothria sb and b; species from Eastern Alps of Austria and Slovenia.................................................................... C. pusillus Beier, 1947

4 Fixed chelal finger with sharp, reclined and spaced teeth increasing in size as far as halfway along the finger, then reduced in size towards the base ( Figs 23–31 ); fixed and movable chelal fingers respectively with 18–32 and 18–30 teeth; ratio of movable finger/hand of chela usually 1.8–1.9 (♂) or 1.6–1.7 (♀); genital opening of male flanked by 9–14 scattered setae on each side ( Fig. 17 )............................................................ C. heterodactylus Tömösváry, 1882

- Fixed chelal finger with distal teeth contiguous, pointed or apically rounded, slightly inclined backwards, followed proximally by large, sharp, reclined and spaced teeth and 9–21 proximal teeth low, contiguous, rounded, reduced in size towards the finger base ( Figs 39–41 ); fixed and movable chelal fingers respectively with 34–50 and 28–38 teeth; ratio of movable finger/hand of chela 2.0–2.2 (♂) or 1.9–2.0 (♀); genital opening of male flanked by 6–8 aligned setae on each side................................................................................................. C. hungaricus Mahnert, 1981

5. Distal half of movable chelal finger (♂♀) with 8–15 triangular, sharp, higher than wide teeth, erect or weakly forward-inclined ( Figs 9–11 )................................................................. C. cavernarum Ellingsen, 1909

- Distal half of movable chelal finger (♂♀) usually with 11–15 low, broad, reclined teeth ( Figs 65–66 , 80–81 ), rarely with 6–10 triangular reclined teeth, wider than high ( Figs 88–89 ).................................. C. raridentatus Hadži, 1930

Figures

FIGURES 1 – 11. Chthonius (C.) cavernarum Ellingsen, 1909. 1 – 3, Anterior margin of carapace of ♂ (Slovenia) (1), ♀ (Slovenia) (2) and ♂ (Italy) (3). 4 – 5, Anterolateral portion of carapace of ♂ (Slovenia) (4) and ♂ (Italy) (5). 6 – 8, Right chelicera of ♂ (Slovenia) (6), ♀ (Slovenia) (7) and ♂ (Italy) (8). 9 – 11, Right chela, lateral view, of ♂ (Slovenia) (9), ♀ (Slovenia) (10) and ♂ (Italy) (11). Figures 1, 2, 4, 6 – 7, 9 – 10: adults from Slovenia, Sviščaki; 3, 5, 8, 11: male from Italy, Grotta di Monteprato.

FIGURES 12 – 19. Chthonius (C.) heterodactylus Tömösváry, 1882, adults from Slovakia, Mt. Vihorlat, no. 27.583. 12 – 13, Anterior margin of carapace of ♂ (12) and ♀ (13). 14, Anterolateral portion of carapace of ♂. 15 – 16, Right chelicera of ♂ (15) and ♀ (16). 17, Genital opening of ♂. 18 – 19, Right chela, lateral view, of ♂ (18) and ♀ (19).

FIGURES 82 – 89. Chthonius (C.) raridentatus Hadži, 1930. 82, Anterior margin of carapace of ♀ (Slovenia, Urhova jama). 83, Anterolateral portion of carapace of ♀ (Slovenia, Urhova jama). 84, Right chelicera of ♀ (Slovenia, Urhova jama). 85 – 89, Right chela, lateral view, of ♀ (Slovenia, Urhova jama) (85), ♂ (Slovenia, Ponikva) (86), ♀ (Slovenia, Ponikva) (87), ♂ (Slovenia, Kočevje) (88) and ♀ (Slovenia, Kočevje) (89). Figures 82 – 85: female from Slovenia, Urhova jama; 86 – 87: adults from Slovenia, Ponikva; 88 – 89: adults from Slovenia, Kočevje.

FIGURES 20 – 26. Chthonius (C.) heterodactylus Tömösváry, 1882. 20, Anterior margin of carapace of ♂ (Romania, Mehádia). 21, Lateral portion of carapace of ♂ (Romania, Mehádia). 22, Left chelicera of ♂ (Romania, Mehádia). 23 – 26, Right chela, lateral view, of ♂ (Romania, Mehádia) (23), ♂ (Romania, Casa de Piatra) (24), ♀ (Romania, Casa de Piatra) (25) and ♀ (Romania, Jara) (26). Figures 20 – 23: male syntype of C. diophthalmus, Romania, Mehádia; 24 – 25: adults from Romania, Casa de Piatra; 26: female holotype of C. leruthi, Romania, Jara.

FIGURES 75 – 81. Chthonius (C.) raridentatus Hadži, 1930. 75 – 76, Anterior margin of carapace of ♂ (holotype) (75) and ♀ (paratype) (76). 77, Anterolateral portion of carapace ♂ (holotype). 78 – 79, Right chelicera of ♂ (holotype) (78) and ♀ (paratype) (79). 80 – 81, Right chela, lateral view, of ♂ (holotype) (80) and ♀ (paratype) (81). Figures 75, 77 – 78, 80: male holotype of C. brandmayri, Slovenia, Mt. Slavnik; 76, 79, 81: female paratype of C. brandmayri, Slovenia, Mt. Slavnik.

FIGURES 42 – 49. Chthonius (C.) lessiniensis Schawaller, 1982. 42 – 43, Anterior margin of carapace of ♂ (42) and ♀ (43) (Italy, Grotta di Monte Capriolo). 44, Anterolateral portion of carapace of ♂ (Italy, Grotta di Monte Capriolo). 45 – 46, Right chelicera of ♂ (45) and ♀ (46) (Italy, Grotta di Monte Capriolo). 47, Fingers of right chelicera of ♂ (Italy, Grotta Bortolomiol). 48 – 49, Right chela, lateral view, of ♂ (movable finger with teratological dentition) (48) and ♀ (movable finger with normal dentition) (49) (Italy, Grotta di Monte Capriolo). Figures 42 – 46, 48 – 49: adults from Italy, Grotta di Monte Capriolo; 47: male from Italy, Grotta Bortolomiol.

FIGURES 50 – 58. Chthonius (C.) pusillus Beier, 1947. 50 – 52, Anterior margin of carapace of ♂ (Austria) (50), ♀ (Austria) (51) and ♂ (Slovenia) (52). 53, Anterolateral portion of carapace of ♂ (Austria). 54 – 55, Right chelicera of ♂ (54) and ♀ (55) (Austria). 56 – 58, Right chela, lateral view, of ♂ (Austria) (56), ♀ (Austria) (57) and ♂ (Slovenia) (58). Figures 50 – 51, 53 – 57: adults from Austria, Weizklamm; 52, 58: male from Slovenia, Šturmova graba.

FIGURES 34–41. Chthonius (C.) hungaricus Mahnert, 1981. 34–35, Anterior margin of carapace of ♂ (34) and ♀ (35) (Romania, Jara, no. 553bis). 36, Anterolateral portion of carapaceof ♂ (Romania, Jara, no. 553bis). 37–38, Right chelicera of ♂ (37) and ♀ (38) (Romania, Jara, no. 553bis). 39–41, Left chela, lateral view, of ♂ (Romania, Jara, no. 553bis) (39), ♀ (Romania, Jara, no. 553bis) (40) and ♀ (Romania, Vălişoara) (41). Figures 34–40: adults from Romania, Jara, no. 553bis; 41: female from Romania, Vălişoara.

FIGURES 59 – 66. Chthonius (C.) raridentatus Hadži, 1930, males from Slovenia, Most na Soči, near Jama pod Smoganico. 59 – 60, Anterior margin of carapace of ♂ (small specimen) (59) and ♂ (large specimen) (60). 61 – 62, Anterolateral portion of carapace of ♂ (small specimen) (61) and ♂ (large specimen) (62). 63 – 64, Right chelicera of ♂ (small specimen) (63) and ♂ (large specimen) (64). 65 – 66, Right chela, lateral view, of ♂ (small specimen) (65) and ♂ (large specimen) (66).