Chthonius (Chthonius) lessiniensis Schawaller 1982
Creators: name: Gardini, Giulio
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Pseudoscorpiones
Chthoniidae
Chthonius
Chthonius lessiniensis

description: Chthonius (C.) lessiniensis Schawaller, 1982
(Figs 42–49, 90)
Chthonius (C.) lessiniensis Schawaller 1982: 49, figs 1–7.
Chthonius (C.) pivai Gardini 1991: 174, figs 8–12 (n. syn.).
Chthonius (Chthonius) pivai: Piva 1997: 158, 166, fig. 158.
Type locality: Italy, Veneto, Verona Prov., Roverè Veronese, Grotta di Monte Capriolo 1071 V /VR (= Gr. Roverè Mille) (45°35′34,4″ N 11°04′ 48,3″E).
Distribution. NE Italy: Venetian pre-Alps.
Diagnosis (♂♀). An anophthalmous hypogean Chthonius (Chthonius) from the Venetian pre-Alps that differs from other species of the heterodactylus group in the following combination of characters: carapace without epistome, chaetotaxy 4:m 4m:4:2:2 (18), rarely m 4m:4:4:2:2 (18); chaetotaxy tergites I–IV: 2:2:4:4; genital opening of male flanked by aligned setae on each side; fixed chelal finger with 21–36 teeth with dental canals, usually without intercalary microdenticles and with distal paraxial seta gradually curved, not enlarged; movable chelal finger with 35–54 triangular, reclined contiguous teeth increasingly reduced towards finger base, reaching back to halfway between sb and b, rarely further back nearer b; coupled sensilla pc of movable chelal finger usually between trichobothria sb and b; chela length 1.29–1.74 (♂) or 1.45–1.89 (♀), movable finger length 0.83–1.03 (♂) or 0.85–1.14 (♀).
Type material examined. ITALY — Veneto: Vicenza Prov. 1 ♂ (holotype of Chthonius (C.) pivai Gardini), Arsiero, Altopiano di Tonezza, Buso del Sasso 1219 V /VI, 840 m a.s.l., 3.VIII.1985, E. Piva leg. (MSNV); 1 ♀ (paratype of Chthonius (C.) pivai Gardini), Velo d’Astico, Massiccio Pasubio–Novegno, Abisso di Mandrina 956 V/VI, 900 m a.s.l., 29.IV.1985, E. Piva leg. (MSNV).
Other material examined. ITALY — Trentino: Trento Prov.— 2 ♂, Folgaria, Bus del Gobo Onzera 207 VT/TN, 1295 m a.s.l., 6.IV.2002, L. Bodei leg.; 1 ♂, id., Lont del Laché 419 VT/TN, 1290 m a.s.l., 30.III.2012, D. Bianco & E. Piva leg. Veneto: Belluno Prov.— 1 ♂, 1 T, Seren del Grappa, Bus de la Tomba 1273 V /BL, 575 m a.s.l., 3.XI.1996, E. Piva leg.; 2 ♂, 1 ♀, id., 3.XI.1996 (EPV); 1 ♂, 1 ♀, id., 15.XII.1996 (EPV); 1 ♀, id., 1.XI.1990, L. Latella & S. Zoia leg. Veneto: Treviso Prov. — 1 ♂, 2 ♀, Possagno, Buco del Dinosauro 1579 V /TV, 935 m a.s.l., 30.VI.1985, E. Piva & I. Ferrari leg.; 1 ♂, id., 14.V.1993, E. Piva leg. (EPV); 1 ♀, id., 24.VIII.1993 (EPV); 1 ♀, Valdobbiadene, Busa de Balcon 1812 V /TV, 1150 m a.s.l., 12.V.1990, M. Grottolo leg.; 1 ♂ (G. Gardini det. 1986), Valdobbiadene, Grotta Bortolomiol 1556 V /TV, 955 m a.s.l., 8.IV.1986, E. Piva leg. (MSNV); 1 es., id., 27.XI.1992, R. Monguzzi leg. (RMM); 1 ♀, id., 8.IV.1995 (RMM); 1 ♂, 4 ♀, id., 28.IV.1996, E. Piva leg. (EPV); 1 ♂, 4 ♀, 2 T, id., 13.IV.1997, G. Peretto & E. Piva leg. (EPV); 1 ♂, 5 ♀, id., 27.VII.1997, E. Piva leg. (EPV); 27 ♂, 16 ♀, 18 T, id., 7.VI.1998, G. Peretto & E. Piva leg. (EPV); 1 ♂, 2 ♀, 1 T, id., 8.XI.1998 (EPV); 10 ♂, 2 ♀, 5 T, id., 11.VII.1999 (EPV); 2 ♀, id., E. Piva leg. (EPV); 1 ♂, id., 10.VI.2001, G. Peretto leg. (EPV); 10 ♂, 5 ♀, 1 T, id., 22.VI.2003, E. Piva leg. Veneto: Verona Prov. — 1 ♂, 1 ♀ (G. Gardini det. 1986), Boscochiesanuova, Grotta dell’Arena 476 V/VR, 1512 m a.s.l., 19.VIII.1983, E. Piva & I. Ferrari leg. (MSNV); 1 ♀, id., 26.IX.1987, M. Grottolo leg.; 1 ♀, id., 26.II.2000; 2 ♀, Boscochiesanuova, Secondo Pozzo di Camporotondo di Sopra 432 V/VR, 1520 m a.s.l., 15.VIII.2003, E. Piva leg. (EPV); 1 ♂, 1 ♀, Boscochiesanuova, Abisso di Lesi 382 V/VR, 1125 m a.s.l., 18.XII.2011, L. Dalle Tezze & G. Zarantonello leg.; 1 ♂, 1 ♀, 3 T, id., 3.VI.2012, L. Dalle Tezze & M. Tommasi leg.; 3 es., Roverè Veronese, Buso del Gatto 1421 V /VR, 685 m a.s.l., 1.VI.1984, R. Monguzzi leg. (RMM); 1 ♂, id., 16.IV.1988, M. Grottolo leg.; 4 es., id., 22.V.1988 (collector not indicated) (MBCG); 1 ♂, 1 ♀, id., 22.V.1988, Comotti & Baldan leg.; 1 T, id., 30.XI.1995, R. Monguzzi leg. (RMM); 2 ♂, 4 ♀, 4 T, Roverè Veronese, Grotta di Monte Capriolo 1071 V /VR (= Gr. Roverè Mille), 1010 m a.s.l., 22.VII.1988, M. Grottolo leg.; 2 ♀, San Mauro di Saline, Spluga Carpenè 396 V/VR, 725 m a.s.l., 5.VI.1983, E. Piva & I. Ferrari leg.; 6 es., id., 4.XII.1988 (collector not indicated) (RMM); 1 ♂, 1 ♀, id., 26.III.1989, Comotti & Baldan leg.; 3 es., id., 26.III.1989 (collector not indicated) (RMM); 2 es., id., 23.III.1990, R. Monguzzi leg. (RMM); 2 ♂, Sant’Anna d’Alfaedo, Grotta Lorenzo Bertola 1120 V /VR, 600 m a.s.l., 2.II.1991, E. Piva & G. Peretto leg. (EPV); 1 ♂, id., 2.IX.2007, E. Piva leg. (EPV); 1 ♂, 1 ♀ (G. Gardini det. 1985), Selva di Progno, Grotta dei Prusti 3 V /VR (= Gr. del Berclie–Perloch), 1150 m a.s.l., 11.XII.1982, E. Piva & I. Ferrari leg. (MSNV); 2 ♀ (G. Gardini det. 1985), id., 8.I.1983 (MSNV); 2 es., id., 8.I.1983 (EPV); 1 ♀, id., 8.I.2012, L. Dalle Tezze & G. Zarantonello leg.; 1 ♀, id., 24.VI.2012, P. Falzirollo leg.; 1 ♀ (G. Gardini det. 1985), Tregnago, Grotta dei Damati 9 V /VR, 600 m a.s.l., 20.II.1983, I. Ferrari leg. (MSNV); 3 ♂, 3 T, Velo Veronese, Covoli di Velo 44 V /VR, 878 m a.s.l., 25.III.1997, G. Peretto & E. Piva leg. (EPV). Veneto: Vicenza Prov.— 1 ♀, Arcugnano, Spruggia dei Cavani 114 V/VI, 154 m a.s.l., 28.XI.1992, E. Piva leg. (EPV); 1 ♀, Arsiero, Buso Alto del Sasso 4047 V/VI, 950 m a.s.l., 7.I.1989, E. Piva leg.; 1 ♀, id., 7.I.1989 (EPV); 1 ♂ (G. Gardini det. 1986), Arsiero, Buso del Sasso 1219 V /VI, 840 m a.s.l., 3.VIII.1985, E. Piva leg. (MSNV); 1 ♀, id., 14.V.1988, E. Piva & I. Ferrari leg. (EPV); 1 ♀, id., 11.VI.1988, E. Piva leg.; 2 ♂, id., 11.VI.1988 (EPV); 1 ♀, Asiago, Lago Bianco, Busa della Vedova n.c., 1350 m a.s.l., 12.VI.2001, M. Cocco et al. leg.; 2 ♂, 1 ♀, id., 17.VI.2012, D. Bianco et al. leg.; 3 ♀, Caltrano, Speluga della Ceresara 62 V /VI, 832 m a.s.l., 14.VII.2006, M. Grottolo leg.; 1 ♂, Lugo Vicentino, Grotta del Nespolo del Mare 3140 V/VI, 292 m a.s.l., 10.II.2002, E. Piva leg. (EPV); 2 T, id., 12.IX.2004, D. Bianco leg. (EPV); 1 ♀, id., 16.VI.2005 (EPV); 1 ♀, Piovene Rocchette, Grotta di Mordifaia 6537 V/VI, 915 m a.s.l., 16.IV.2005, D. Bianco leg. (EPV); 1 ♀, id., 10.XII.2005; 1 ♀, id., 30.VIII.2006, D. Bianco & A. Casa leg. (EPV); 2 ♂, 1 ♀, id., 11.VIII.2009, D. Bianco & G. Martini leg.; 3 ♂, 1 ♀, 2 T, id., 8.VIII.2011; 1 ♂, id., 7.III.2012, D. Bianco & E. Piva leg.; 1 ♂, Recoaro Terme, Grotta del Giro 2282 V /VI, 730 m a.s.l., 15.XII.2009, D. Bianco & G.P. Rossi leg.; 1 ♀, Recoaro Terme, Grotta Buson del Forcellin 6556 V/VI, 1890 m a.s.l., 8.VII.2004, D. Bianco & N. Righetto leg. (EPV); 1 T, id., Grotta Città di Roccia 7723 V/VI, 1377 m a.s.l., 9.X.2012, D. Bianco, E. Piva & G.P. Rossi leg.; 1 ♀, Rotzo, Voragine delle Banchette 104 V/VI, 680 m a.s.l., 18.XI.1989, E. Piva leg. (EPV); 1 ♂, 1 T, Schio, Pozzo di San Patrizio 6542 V/VI, 460 m a.s.l., 30.XII.2001, F. Pretto & N. Righetto leg. (EPV); 1 ♂, id., 1.XI.2002, N. Righetto, E. Piva & D. Bianco leg. (EPV); 3 ♂, 1 ♀ 1 T, id., 2.I.2003, D. Bianco, F. Casa & N. Righetto leg. (EPV); 1 ♀, id., 2.VII.2004, N. Righetto leg. (EPV); 6 ♂, 2 ♀, id., 27.V.2007, D. Bianco & N. Righetto leg. (EPV); 1 ♂, 5 ♀, id., 1.XII.2007; 2 ♂, id., 2.X.2008; 1 ♀, id., 17.III.2010, D. Bianco, F. Casa & N. Righetto leg.; 1 ♂, 4 ♀, Schio, Santa Maria del Tretto, Grotta Busa Freda, 395 m a.s.l., 2.XII.2004, D. Bianco leg. (EPV); 1 ♂, 2 ♀, id., 18.XI.2005 (EPV); 1 ♂, 1 ♀, id., 18.XI.2005, D. Bianco & A. Casa leg. (EPV); 1 ♀, id., 4.V.2006, D. Bianco leg. (EPV); 2 ♂, 1 ♀, id., 11.XII.2006; 1 ♀, id., 19.I.2008, D. Bianco & A. Casa leg.; 3 ♂, 5 ♀, id., 11.X.2008, D. Bianco leg.; 5 ♂, 4 ♀, id., 14.III.2009, D. Bianco leg.; 1 ♀, id., 1.X.2010, D. Bianco & G.P. Rossi leg.; 1 ♀, Schio, Prima Voragine del Bosco delle Mole 643 V/VI, 700 m a.s.l., 4.III.2007, E. Piva leg. (EPV); 2 ♂, 2 ♀, Schio, San Ulderico, Buso Nicola n.c., 670 m a.s.l., 2.X.2009, D. Bianco & A. De Munari leg.; 5 ♂, 1 ♀, id., Abisso Righetto n.c., 640 m a.s.l., 26.IX.2010; 1 ♂, id., 26.IX.2012, A. De Munari leg.; 1 ♂, Torrebelvicino, Grotta aù del Sindio 2472 V /VI, 770 m a.s.l., 10.IV.2001, D. Bianco leg. (EPV); 3 ♂, 1 ♀ (G. Gardini det. 1986), Valstagna, Covol o Cogol dei Siori 600 V/ VI, 150 m a.s.l., 23.IV.1983, E. Piva & I. Ferrari leg. (MSNV); 2 ♀ (G. Gardini det. 1985), id., 21.V.1983 (MSNV); 1 ♀, id., 8.IV.1995, M. Grottolo leg.
Description of adults (♂♀). Highly specialized, troglomorphic facies; integument without pigmentation; hispid granulation on lateral surfaces of carapace, on cheliceral palm and on distal half of chelal hand. Carapace 1.0–1.1 times longer than broad, constricted posteriorly; anterior margin (Figs 42–43) without epistome, with denticles between median macrosetae; ocular area as in Fig. 44, no eyes or eye-spots; 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; length of anteromedian and anterolateral macrosetae respectively 0.12–0.16 and 0.04–0.09 mm, length of median macrosetae of ocular row 0.21–0.26 mm, length of posterior macrosetae 0.12–0.18 mm. Usual chaetotaxy of tergites I–X 2:2:4:4:4:6:6:6:6:4; tergite II rarely with 3 setae, tergite V rarely with 5 setae. Usual chaetotaxy of sternites II–X 9–10:(3)10(3):(1)7–9(1):8:7:7:7:7:7–8; sternite II rarely with 8 or 11 setae, III rarely with 9 or 11 setae, IV rarely with 10 setae and 2 stigmatal microsetae, V rarely with 7 or 9 setae; genital opening of males flanked by 8–9 (rarely 10 or 13) setae on each side (usually aligned, rarely partly scattered). Chelicera (Figs 45–47) 2.4–2.6 (♂♀) times as long as broad, palm with 6 (rarely 5 or 7) setae and 2 (rarely 3) microsetae laterally; fixed finger with 7–12 teeth (the apical one and the third from last larger) and 3–7 proximal microtubercles; movable finger with an isolated subapical tooth (di) usually level with the spinneret in males, but proximad of the spinneret in females; 6–10 teeth proximally reduced in size and 4–10 basal tubercles; gl ratio 0.54–0.62; spinneret triangular (Fig. 47), rarely apically rounded in males (Fig. 45), larger, prominent and apically rounded in females (Fig. 46); rallum with 11 blades; serrulae interior and exterior respectively with 12–15 and 17–19 blades. Coxal setae: pedipalp 5 (including 2 on manducatory process), I 4 + 3 marginal microsetae (rarely 3 + 2 marginal microsetae), II 5 (rarely 4), III 6 (rarely 5), IV 6 (rarely 5 or 7); coxa II with 9–19 (usually 13–15) coxal spines, coxa III with 2–5 (usually 3–4) coxal spines; intercoxal tubercle bisetose. Pedipalp: femur 7.7–8.8 (♂) or 6.9–8.5 (♀) times as long as broad; chela (Figs 48–49) 6.6–7.6 (♂) or 6.1–7.3 (♀) times as long as deep; hand of chela 2.3–2.5 (♂) or 2.15–2.45 (♀) times as long as deep, weakly depressed proximad of ib/isb; fixed chelal finger with marked sigmoid curvature in lateral view, with 21–36 teeth with dental canals, usually without intercalary microdenticles; first tooth reduced and level with trichobothria dx/et (rarely distad of dx); 17–33 large, sharp, weakly reclined teeth increasing in size as far as halfway along the finger, then reduced in size towards finger base; 1–4 small proximal teeth with rounded tips; base of fixed chelal finger with 0–6 microtubercles; fixed finger at level of it/est with 3–4 teeth occupying 0.1 mm (distance between successive apices 0.027–0.055 mm); tip of fixed chelal finger with apical sensilla af1 ‾ 2, distal paraxial seta gradually curved, not enlarged; movable chelal finger with 35–54 triangular, reclined, contiguous teeth increasingly reduced towards finger base, reaching back to halfway between sb and b, rarely further back nearer b; 2–4 proximal teeth small and with rounded tips; coupled sensilla pc usually nearer to sb than to b, rarely halfway between sb and b or distad of sb; tip of movable chelal finger with apical sensilla am1 ‾ 2; trichobothria as in Figs 48–49, ist distad of line eb/esb; ratio of movable finger/hand of chela 1.6–1.9 (♂) or 1.5–1.8 (♀); ratio of pedipalpal femur/movable finger 1.1–1.2 (♂♀); ratio of pedipalpal femur/carapace 1.85–2.15 (♂) or 1.75–2.05 (♀).
Measurements (in mm). Body length 1.6–2.0 (♂) or 1.7–2.4 (♀). Carapace 0.44–0.61 × 0.40–0.56 (0.43–0.53 anteriorly) (♂) or 0.52–0.65 × 0.45–0.63 (0.47–0.60 anteriorly) (♀). Chelicera 0.445–0.58 × 0.18–0.23 (♂) or 0.51–0.64 × 0.21–0.26 (♀); movable finger length 0.22–0.28 (♂) or 0.25–0.32 (♀). Pedipalp: femur 0.86–1.17 × 0.11–0.14 (♂) or 0.99–1.28 × 0.12–0.16 (♀); chela 1.29–1.74 × 0.175–0.235 (♂) or 1.45–1.89 × 0.23–0.275 (♀); hand length 0.42–0.58 (♂) or 0.49–0.64 (♀); fixed finger length (from tip to eb) 0.87–1.11 (♂) or 0.93–1.24 (♀); movable finger length 0.83–1.03 (♂) or 0.85–1.14 (♀).
Description of tritonymph. Integument without pigmentation, hispid granulation as in adults. Carapace 1.0–1.2 times longer than broad, form of anterior margin as in adults; no eyes or eye-spots; chaetotaxy 4:m 4m:4:2:2 (18), rarely anterior row with one microchaeta, or median and intermediate rows with 3 macrosetae; length of anteromedian and anterolateral macrosetae respectively 0.09–0.12 and 0.05–0.06 mm, length of median macrosetae of the ocular row 0.18–0.23 mm, length of posterior macrosetae 0.13–0.15 mm. Chaetotaxy of tergites as in adults. Chaetotaxy of sternites II–IX 5–6:(2)6–8(2):(1)6–8(1):7:7:7:7:7. Chelicera 2.3–2.6 times as long as broad, palm with 5 setae and 2 microsetae laterally; fixed finger with 8–9 teeth, the first two larger, the following, proximally reduced in size, and 4–5 proximal microtubercles; movable finger with an isolated subapical tooth (di) proximad of the spinneret and 5–7 teeth; gl ratio 0.55–0.60; spinneret prominent and apically rounded, as in females; rallum with 9 blades; serrulae interior and exterior respectively with 12 and 15 blades. Coxal setae: pedipalp 5 (including 2 on manducatory process), I 3 + 2 marginal microsetae, II 4, III 5, IV 5; coxae I rarely with 3 marginal microsetae, coxae IV rarely with 4 setae; coxa II with 8–10 coxal spines, coxa III with 3–4 coxal spines; intercoxal tubercle bisetose. Pedipalp: femur 6.5–7.1 times as long as broad; chela 6.4–7.3 times as long as deep; hand of chela 2.3–2.4 times as long as deep; fixed chelal finger with 22–31 teeth with dental canals, without intercalary microdenticles; first tooth reduced and level with trichobothria dx; 1–2 small proximal teeth with rounded tips; base of fixed chelal finger with few microtubercles; fixed finger at level of it/est with 3 (rarely 4) teeth occupying 0.1 mm (distance between successive apices 0.025–0.036 mm); distal paraxial seta gradually curved, not enlarged; movable chelal finger with 31–42 triangular, reclined teeth, increasingly reduced towards the finger base, reaching back to trichobothrium b; coupled sensilla pc distad of b; ratio of movable finger/hand of chela 1.6–1.9; ratio of pedipalpal femur/movable finger 1.0–1.2; ratio of pedipalpal femur/carapace 1.70–1.75.
Measurements (in mm). Body length 1.4–1.55. Carapace 0.445–0.475 × 0.37–0.47 (0.35–0.46 anteriorly). Chelicera 0.41–0.45 × 0.16–0.18, movable finger length 0.20–0.22. Pedipalp: femur 0.78–0.83 × 0.11–0.12; chela 1.15–1.25 × 0.16–0.18; hand length 0.39–0.42; fixed finger length (from tip to eb) 0.73–0.83; movable finger length 0.66–0.80.
Remarks. Chthonius lessiniensis was described by Schawaller (1982) from one male from the Venetian cave of Grotta Roverè Mille (= Gr. di Monte Capriolo 1071 V /VR, Roverè Veronese) and compared to C. irregularis Beier, 1961 [latter subsequently synonymized with C. ligusticus Beier, 1930 by Gardini & Oggianu (1992)], C. lanzai di Caporiacco, 1947, C. elongatus Lazzeroni, 1970 and C. magnificus Beier, 1938. Examination of specimens of both sexes from the type locality of C. lessiniensis reveals some discrepancies with the description of Schawaller (1982): the most important concern the chaetotaxy of carapace [m 4m:m 4m:4:2:2 (16) according to Schawaller’s drawing (1982: fig. 1); 4:m 4m:4:2:2 or rarely m 4m:4:4:2:2 (16) here], the chaetotaxy of tergite VI [4 setae in Schawaller (1982), 6 setae here], the number of setae flanking the male genital opening [5–6 in Schawaller (1982), 8–9 (rarely 10–13) here] and measurements of pedipalpal chela [male chela breadth 0.26 mm, 6.1 times as long as broad in Schawaller (1982), depth 0.175–0.235 mm, 6.6–7.6 times as long as deep here]. The discrepant characteristics reported by Schawaller (1982) are not included in the above description of C. lessiniensis.
Gardini (1991) described Chthonius pivai from a male and a female, collected from caves in Veneto (type locality: Buso del Sasso 1219 V /VI, Arsiero), and compared it to C. lessiniensis, C. brandmayri Callaini, 1986 and C. magnificus. The characters proposed by Gardini (1991) to differentiate C. pivai from C. lessiniensis —larger dimensions and slender appendages, different number of setae in anterior row of carapace and along genital opening—mostly fall within the range of variation now observed in C. lessiniensis. The sole remaining difference concerns the number of setae of the male genital opening, but this cannot be considered sufficient to separate two species. Chthonius pivai Gardini, 1991 is therefore considered here to be a junior subjective synonym of Chthonius lessiniensis Schawaller, 1982 (n. syn.).
Chthonius lessiniensis is a subterranean species, showing a high degree of troglomorphy, ranging from the western Venetian pre-Alps (= Vicenza pre-Alps) to the eastern Venetian pre-Alps (= Belluno pre-Alps) (Fig. 90). Among the species of the C. heterodactylus group, the affinities of C. lessiniensis are uncertain, but it seems to be related to the hypogean C. magnificus from Bosnia-Herzegovina and Croatia. Both species share a similar chaetotaxy of tergites I–IV (2:2:4:4), a similar type of dentition of the fixed and movable chelal fingers, and have two setae in the posterior row of the carapace. Differences between C. lessiniensis and C. raridentatus, which are parapatric in NE Italy, are given in the above key.
description: Published as part of Gardini, Giulio, 2014, The species of the Chthonius heterodactylus group (Arachnida, Pseudoscorpiones, Chthoniidae) from the eastern Alps and the Carpathians, pp. 101-137 in Zootaxa 3887 (2) on pages 117-121, DOI: 10.11646/zootaxa.3887.2.1, http://zenodo.org/record/228058