Neobisium (Neobisium) sardoum Beier, 1956

Gardini, Giulio, 2023, The troglomorphic pseudoscorpions of the genus Neobisium from Corsica, Sardinia and mainland Italy, with description of new species (Pseudoscorpiones: Neobisiidae), Zootaxa 5381 (1), pp. 1-67 : 19-25

Neobisium (Neobisium) sardoum Beier, 1956

( Figs 31–44 , 118 )

Neobisium (Ommatoblothrus) sardoum Beier, 1956b: 132 , figs 1–2.

Type locality: Italy, Sardinia, Nuoro Province, Oliena, Grotta de S’Abba Medica 335 Sa / NU (40°16’11.3”N 9°26’24.6”E) .

Distribution. Italy (Sardinia).

Diagnosis (♂ ♀). A subterranean, troglomorphic Neobisium from Sardinia (Supramonte) that differs from other Mediterranean species of the genus in the following combination of characters: posterior margin of carapace with 6 (rarely 7) setae, epistome triangular, anterior eyes with weakly convex lens, dark integument between anterior and posterior eyes absent; tergites I–IV: 6–7:6–7:6–9:7–9; cheliceral palm with 6 (rarely 7) setae, rallum with 8–9 (rarely 10) blades; fixed chelal finger irregularly heterodentate, with contiguous teeth; fixed and movable chelal fingers with 109–120 and 84–97 teeth, respectively; pedipalpal femur 1.94–2.26 mm length (6.36–7.32 ×), patella 1.40–1.71 mm (4.05–4.83 ×), movable finger 1.99–2.36 mm; pedipalpal hand with long oval profile and its greatest width in the proximal third; fingers curved in dorsal view, slightly curved in antiaxial view; ratio between movable chelal finger and chelal hand with pedicel 1.30–1.61; ratio between pedipalpal femur and movable chelal finger 0.88–1.05; ratio between pedipalpal femur and carapace 1.73–2.20; trichobothrium ist distal st or rarely at level of st, closer to the finger tip than to isb.

Type material examined. ITALY — Sardinia: Nuoro Prov. : 2♀ 1D syntypes (1♀ with missing right chelicera and 1♀ with right chelicera and pedipalp dissected by Beier), “ Neobisium (Ommatoblothrus) sardoum n. sp. / det. Beier Paratypen / Sardinia, Gr. S’Abba [Grotta de S’Abba Medica 335 Sa/ NU] / Oliena, 5.4.1956.” “27205” ( NHMW) .

Non-type material examined. ITALY — Sardinia: Nuoro Prov.: 1 T, Dorgali, Codula di Luna, Teletottes, Grotta su Palu ( Sistema della Codula Ilune 1988 Sa / NU) (40°10’38.2”N 9°33’50.5”E), 185 m a.s.l., 27.V.1993, A. Casale leg. ; 1 T, id., 8.VIII.2021, G. Trezzi leg. ; 1♀, Oliena, Supramonte di Oliena, Orgoi , Grotta Orgoi 34 Sa / NU (40°15’36.2”N 9°27’29.3”E), 997 m a.s.l., 22.IV.1964, V. Sbordoni leg. (M. Beier det.) ( MZUR) ; 1♂, Oliena, Supramonte di Oliena, Sos Ostis , Grotta Sa Nurra de Sas Palumbas 217 Sa / NU (40°15’29”N 9°26’11,3”E), 1220 m a.s.l., 22.IV.1964, V. Sbordoni leg. (M. Beier det.) ( MZUR) ; 1♂, id., 17. VI.1985, D. Baratelli leg.; 1♀, id., 30.IV.1991, E. Piva leg.; 1♂, id., 10. V.1993, L. Latella leg.; 1♀, id., 23. V.1993, A. Molinu leg.; 1♀, id., 6.II.1996, L. Latella leg.; 1♀, id., 27.X.2007, E. Lana & P. Marcia leg.; 1D, Oliena, Supramonte di Oliena, Sos Ostis , Grotta Nurra ‘e Pradu 3083 Sa / NU (40°15’26.7”N 9°25’45.5”E), 1223 m a.s.l., 8. VI.2007, P. Marcia leg. ; 1D, id., 8.XI.2009, P. Marcia leg.; 1♀, Oliena, Supramonte di Oliena, Grotta Stupidi e Malprotetti n.c. (40°15’38”N 9°25’31”E), 1100 m a.s.l., 18. VI.2006, P. Marcia leg. ; 1♀, Orgosolo, Supramonte di Orgosolo, Valle Flumineddu , Grotta Piggios de Su Mudrecu n.c. (connected with the karst complex S’Orale su Mudrecu , or VPF 2777 Sa / NU) (40°08’38.70”N 9°27’37.80”E), 809 m a.s.l., 20.VIII.2009, C. Corongiu leg. ; 1♂, Urzulei, Supramonte di Urzulei, Costa Silana , Monte Su Nercone , Voragine di Su Nercone 1175 Sa / NU (40°08’12.6”N 9°30’12.6”E), 1170 m a.s.l., 21.III.1999, M. Mucedda leg. ; 1♂, id., 24.X.1999, M. Mucedda leg.; 1♂ 1D, id., 13. V.2003, E. Lana & A. Molinu leg.; 1♀, Urzulei, Supramonte di Urzulei, Bacu de su Carcuri , Grotta Suttaterra de Sarpis 268 Sa / NU (40°10’50.2”N 9°32’39.5”E), 800 m a.s.l., 28.XI.1993, M. Mucedda leg. ; 1♂, Urzulei, Supramonte di Urzulei, Codula Orbisi , Costa ‘e Monte , Grotta del Portello 3720 Sa / NU (40°10’25.9”N 9°29’30.1”E), 765 m a.s.l., 3.IV.1994, M. Marrosu leg. ; 1♂, id., 14.IX.1997, G. Dore & A. Chessa leg.; 2♂, Urzulei, Supramonte di Urzulei, Codula Orbisi , Inghiottitoio di Orbisi 398 Sa / NU (40°09’47.2”N 9°29’21”E), 780 m a.s.l., 27.VII.1996, R. Spiga leg. ; 1♀, Urzulei, Supramonte di Urzulei, Colostrargiu , Su Colostrargiu 2623 Sa / NU (40°08’08.4”N 9°27’01.6”E), 825 m a.s.l., 21.IV.2006, P. Marcia leg. ; 1♂, Urzulei, Supramonte di Urzulei, Mamucone , Grotta II di Su Mamucone o Sa Rutta ‘e Su Cardu 385 Sa / NU (40°05’40.6”N 9°26’50”E), 974 m a.s.l., 27.IX.1992, A. Molinu leg. ; 1♂, Urzulei, Supramonte di Urzulei, Mannaresuru , Rutta de Mannaresuru 2267 Sa / NU (40°07’44.6”N 9°26’50”E), 860 m a.s.l., 7.X.2012, P. Marcia leg. ; 1♂, id., 6.I.2000, M. Mucedda leg.; 2♂ 1♀, Urzulei, Supramonte di Urzulei, Valle Flumineddu , Grotta Su Conti n.c., 3.X.1999, C. Onnis leg.

Description of adults (♂ ♀) (in square brackets data relating to ♀ syntype). Carapace, chelicerae, pedipalps and palpal coxae red-brown; pedipalps smooth, pleural membrane granular. Carapace 1.29–1.52 (♂ ♀) times as long as broad, with four eyes without tapetum ( Fig. 31 ) (with weak tapetum, following Beier 1956b), the anterior ones with weakly convex lens (diameter 0.09–0.11 mm), the posterior ones reduced, with weak lens (diameter 0.08–0.11 mm); distance from anterior eyes to anterior margin of carapace 0.09–0.11 mm, distance from anterior to posterior eyes 0.035 –0.045 mm; dark integument between anterior and posterior eyes absent; anterior margin with prominent triangular epistome, apically rounded or acuminate ( Fig. 31 ); 22 macrosetae, anterior and posterior rows with 4 and 6 (rarely 7) macrosetae, respectively, besides 1 (rarely 2) preocular seta on each side. Chaetotaxy of tergites I–X (♂ ♀): 6–7:6–7:6–9:7–9:8–11:9–11:9–11:9–11:8–10:8–11. Chaetotaxy of sternites II–X (♂): 14– 22:(3)44–56(3):(3)13–17(3):14–17:13–16:13–15:14:13–15:12–13, median genital sac pyriform, 0.30–0.35 mm long, reaching the middleof sternite V; chaetotaxy of sternites II–X (♀): 6–14:(3)30–31(3):(3)13–14(3):14–16:13– 15:14:14–16:14–15:14–16. Chelicera ( Fig. 32 ) 1.95–2.07 (♂ ♀) times as long as broad, palm with 6 setae (6 and 7 in ♂ from Rutta de Mannaresuru); fixed finger with 13–18 subequal teeth proximally and distally decreasing in size; movable finger with 12–16 subequal teeth and a prominent tooth at level of gs; gs ratio 0.67–0.76, spinneret largely prominent and rounded, with 6–7 silk ducts; rallum with 8 or 9 (rarely 10: ♂ from Sa Nurra de Sas Palumbas) blades, the distal one laterally pinnate and isolated on a prominence, the second one serrate, the successive ones smooth, the proximal shorter; serrulae interior and exterior with ca 26–30 and 34–35 blades, respectively. Manducatory process with 5 setae. Coxal setae: pedipalp 10–14, I 8–10, II 8–10, III 6–8, IV 13–18; anterolateral process of coxa I squat, apically pointed (rarely obtuse), anteromedial process rounded with denticles ( Fig. 33 ). Pedipalp ( Figs 34–36 ): trochanter 2.58–2.96 (♂ ♀) times as long as broad, with 2–3 weak button-like tubercles (with lyrifissure) on antiaxial face; femur 6.36–7.32 (♂) or 6.55–7.07 (♀) times as long as broad, weakly enlarged distally, with many dorsal glandular pores; patella 4.05–4.83 (♂) or 4.44–4.73 (♀) times as long as broad, club gradually enlarged distally, ratio between club and pedicel 2.2–2.65 (♂) or 2.04–2.23 [2.25] (♀), ratio X/Y = 0.34–0.39 (♂ ♀); chela with pedicel 6.0–6.36 (♂) or 6.10–6.45 [5.78] (♀) times as long as broad; fingers curved in dorsal view, slightly curved in antiaxial view ( Figs 35–36 ); hand of chela with pedicel 2.48–3.06 (♂) or 2.60–2.63 [2.50] (♀) times as long as broad, with long oval profile and its greatest width in the proximal third (dorsal view); fixed chelal finger irregularly heterodentate ( Fig. 36 ), with 109–120 (♂ ♀) pointed contiguous teeth, nodus ramosus subterminal; movable chelal finger with 84–97 (♂ ♀) low, flattened contiguous teeth ( Fig. 36 ), apart from the last 10–12 distal which are cuspidate; all teeth with dental canals; sensillum just proximad or at level of st; trichobothria as in figs 35–36 and figs 38–41; relative position of trichobothria along chelal axis (♂ ♀): it 0.08–0.11/ et 0.11–0.13/ est 0.12 – 0.17/ ist 0.23–0.28/ isb 0.84–0.87/ ib 0.87–0.90/ esb 0.93–0.96/ eb 0.95–0.97/ t 0.16–0.18/ st 0.27–0.32/ sb 0.72–0.84/ b 0.89–0.92; trichobothrium est at level of t or distal t; trichobothrium ist distal st or rarely at level of st, closer to the finger tip than to isb; trichobothrium isb proximal sb; ratio between movable finger and hand of chela with pedicel 1.30–1.55 (♂) or 1.43–1.61 (♀); ratio between pedipalpal femur and movable finger 0.88–1.05 (♂ ♀); ratio between pedipalpal femur and carapace 1.73–2.20 (♂ ♀). Leg IV ( Fig. 37 ): trochanter 2.97–3.06 (♂) or 2.82–3.0 (♀) times as long as deep, femur + patella 6.32–6.64 (♂) or 5.93–6.17 (♀) times as long as deep, tibia 9.75–10.35 (♂) or 9.7–10.0 (♀) times [TS = 0.30–0.32 (♂) or 0.30–0.40 (♀)], basitarsus 5.30–6.64 (♂) or 5.85–6.43 (♀) times [TS = 0.12–0.14 (♂) or 0.12–0.135 (♀)], telotarsus 7.91–9.09 (♂) or 8.0–9.1 (♀) times as long as deep [TS = 0.58–0.61 (♂) or 0.60–0.64 (♀)], ratio between basitarsus and telotarsus (♂ ♀) 0.75–0.92, subterminal seta furcate, claws with small dorsal tooth.

Measurements. Body length 3.7–4.0 (♂ ♀). Carapace 0.98–1.29 × 0.69–0.98 anteriorly (♂) or 1.10–1.14 × 0.78–0.83 anteriorly (♀). Chelicera 0.69–0.84 × 0.34–0.43 (♂) or 0.76–0.84 × 0.385 –0.405 (♀); movable finger length 0.45–0.655 (♂) or 0.495–0.54 (♀). Pedipalp: trochanter 0.75–0.91 × 0.27–0.32 (♂) or 0.83–0.88 [0.94] × 0.29–0.30 [0.345] (♀); femur 1.94–2.26 × 0.27–0.355 (♂) or 1.98–2.12 [2.27] × 0.28–0.305 [0.34] (♀); patella 1.40–1.71 × 0.29–0.395 (♂) or 1.49–1.60 [1.63] × 0.315–0.36 [0.365] (♀); chela with pedicel 3.18–3.72 × 0.50– 0.62 (depth 0.49–0.60) (♂) or 3.42–3.66 [3.70] × 0.53–0.60 [0.64] (depth 0.51–0.60 [0.65]) (♀); hand with pedicel length 1.34–1.60 (♂) or 1.38–1.56 [1.60] (♀); movable finger length 1.99–2.36 (♂) or 2.16–2.23 [2.27] (♀). Leg IV: trochanter 0.62–0.69 × 0.205 –0.225 (♂) or 0.65–0.72 × 0.23–0.24 (♀); femur + patella 1.69–1.96 × 0.265 –0.295 (♂) or 1.79–1.96 × 0.29–0.33 (♀); tibia 1.55–1.76 × 0.15–0.17 (♂) or 1.60–1.79 × 0.16–0.18 (♀); basitarsus 0.69–0.83 × 0.11–0.13 (♂) or 0.74–0.82 × 0.115–0.14 (♀); telotarsus 0.76–1.0 × 0.095 –0.115 (♂) or 0.91–1.0 × 0.10–0.25 (♀).

Description of tritonymph from Grotta su Palu (Dorgali). Carapace, chelicerae, pedipalps and palpal coxae red-brown pale. Pedipalps smooth, pleural membrane granular. Carapace 1.5 times as long as broad, with four eyes without tapetum ( Fig. 42 ), the anterior ones with convex lens (diameter 0.09 mm), the posterior ones reduced, with weak lens (diameter 0.09 mm); distance from anterior eyes to anterior margin of carapace 0.07 mm, distance from anterior to posterior eyes 0.025 mm; anterior margin of carapace with a triangular epistome, apically blunt ( Fig. 42 ); 20 macrosetae, anterior and posterior rows with 4 and 5 (presumably 6) macrosetae, respectively, besides 1 preocular seta on each side. Chaetotaxy of tergites I–X 6:7:8:9:10:9:8:8:10:7. Chaetotaxy of sternites II–X: 2?:(3)14(3):(3)11(3):15:13:14:14:14:12. Chelicera 1.98 times as long as broad, palm with 5 or 6 setae, fixed finger with subequal worn teeth, movable finger with a prominent tooth just distad of gs; gs ratio 0.70, spinneret largely prominent and rounded, with 6 silk ducts; rallum with 7 blades, the distal one laterally pinnate and isolated on a prominence, the second one serrate, the successive ones apparently smooth, the proximal shorter; serrulae interior and exterior with ca 27 and 30 blades, respectively. Manducatory process with 3 setae. Coxal setae: pedipalp 7, I 5–7, II 5, III 6, IV 8–9; anterolateral process of coxa I squat, apically pointed. Pedipalp: trochanter 2.2 times as long as broad; femur 6.3 times as long as broad, weakly enlarged distally; patella 4.0 times as long as broad, weakly and gradually enlarged distally, club 2.26 times longer than pedicel, ratio X/Y = 0.5; chela with pedicel 6.05 times as long as broad; hand of chela with pedicel 2.47 times as long as broad; fixed chelal finger irregularly heterodentate, with 96 pointed contiguous teeth, nodus ramosus subterminal; movable chelal finger with 81 low, flattened contiguous teeth, apart from the last 10 distal which are cuspidate; all teeth with dental canals; sensillum not seen; relative position of trichobothria along chelal axis: it 0.12/ et 0.15/ est 0.19 / ist 0.28/ ib 0.86/ esb 0.91/ eb 0.94/ t 0.21/ st 0.50/ b 0.90; ratio between movable finger and hand of chela with pedicel 1.57; ratio between pedipalpal femur and movable finger 0.89; ratio between pedipalpal femur and carapace 1.50. Leg IV: trochanter 2.5 times as long as deep, femur + patella 5.14 times as long as deep, tibia 9.39 times (TS = 0.33), basitarsus 4.9 times (TS = 0.12), telotarsus 6.09 times as long as deep (TS = 0.53), ratio between basitarsus and telotarsus 0.73, subterminal seta furcate, claws without (?) dorsal tooth.

Measurements. Body length 3.35. Carapace 0.93 × 0.62 anteriorly. Chelicera 0.575 × 0.29, movable finger length 0.37. Pedipalp: trochanter 0.52 × 0.235; femur 1.40 × 0.22; patella 1.01 × 0.25; chela with pedicel 2.45 × 0.405 (depth 0.415); hand with pedicel length 1.0; movable finger length 1.57. Leg IV: trochanter 0.45 × 0.18; femur + patella 1.21 × 0.235; tibia 1.08 × 0.115; basitarsus 0.49 × 0.10; telotarsus 0.67 × 0.11.

Description of deutonymphs from Grotta Nurra ‘e Pradu (Oliena) and Voragine Su Nercone (Urzulei). Integuments pale. Pedipalps smooth, pleural membrane granular. Carapace 1.31–1.34 times as long as broad, with four eyes without tapetum ( Fig. 43 ), the anterior ones with convex lens (diameter 0.065 mm), the posterior ones reduced to a withe spot (diameter 0.055 mm); distance from anterior eyes to anterior margin of carapace 0.05 mm, distance from anterior to posterior eyes 0.020 mm; anterior margin of carapace with a slightly prominent, broadly rounded epistome ( Fig. 43 ); anterior and posterior rows with 4 and 6 macrosetae, respectively, preocular setae not seen. Chaetotaxy of tergites I-X 6:6:6:6:7:7:8:7:8:8. Chaetotaxy of sternites II–X: 0:(2)4(2):(2)4(2):8:9:8:8:9:8. Chelicera 1.88–1.92 times as long as broad, palm with 5 setae, fixed finger with 18–19 subequal teeth, movable finger with 12–13 teeth, one of which prominent just distad of gs; gs ratio 0.62–0.66, spinneret largely prominent, hemispheric, with 4 silk ducts; rallum with 6 blades, the distal one laterally pinnate and isolated on a prominence, the second one serrate, the successive ones apparently smooth, the proximal shorter; serrulae interior and exterior with ca 22 and 26 blades, respectively. Manducatory process with 3 setae. Coxal setae: pedipalp 7, I 4, II 5, III 4, IV 5; anterolateral process of coxa I squat, apically pointed. Pedipalp: trochanter 2.25–2.27 times as long as broad; femur 5.29–5.46 times as long as broad; patella 3.11–3.15 times as long as broad, weakly and gradually enlarged distally, club 1.8–1.95 times longer than pedicel, ratio X/Y = 0.65; chela with pedicel 4.89–5.09 times as long as broad; hand of chela with pedicel 2.15–2.22 times as long as broad; fixed chelal finger irregularly heterodentate ( Fig. 44 ), with 64–68 pointed contiguous teeth, nodus ramosus subterminal; movable chelal finger with 57–60 low, flattened contiguous teeth, apart from the last 8–10 distal which are cuspidate ( Fig. 44 ); all teeth with dental canals; sensillum halfway between b–t or closer to t than to b; relative position of trichobothria along chelal axis: it 0.17–0.19/ et 0.23–0.24/ est 0.29 –0.30/ ist 0.36–0.39/ ib 0.83–0.84/ eb 0.89/ t 0.32–0.36/ b 0.85; ratio between movable finger and hand of chela with pedicel 1.42–1.49; ratio between pedipalpal femur and movable finger 0.90; ratio between pedipalpal femur and carapace 1.36–1.38. Leg IV: trochanter 2.56–? times as long as deep, femur + patella 5.06–5.17 times as long as deep, tibia 6.55–6.84 times (TS = 0.28–0.34), basitarsus 3.8–4.0 times (TS = 0.12–0.17), telotarsus 6.0 times as long as deep (TS = 0.32–0.38), ratio between basitarsus and telotarsus 0.67–0.71, subterminal seta furcate, claws with a very small dorsal tooth.

Measurements. Body length 2.0. Carapace 0.59–0.66 × 0.45–0.49 anteriorly. Chelicera 0.395 –0.425 × 0.205 – 0.225, movable finger length 0.245–0.27. Pedipalp: trochanter 0.36–0.41 × 0.16–0.18; femur 0.82–0.90 × 0.17–0.17; patella 0.56–0.63 × 0.18–0.20; chela with pedicel 1.40–1.59 × 0.275 –0.325 (depth 0.27–0.315); hand with pedicel length 0.61–0.70; movable finger length 0.91–1.0. Leg IV: trochanter?–0.32 ×?–0.125; femur + patella 0.74–0.81 × 0.145–0.16; tibia 0.59–0.65 × 0.09–0.095; basitarsus 0.285–0.32 × 0.075–0.08; telotarsus 0.42–0.45 × 0.07–0.075.

Remarks. Neobisium sardoum ―the type species of the subgenus Ommatoblothrus Beier, 1956 ―was described from four specimens of both sexes (“Typen: 4 ♂ ♀ ”) from the cave Grotta de S’Abba Medica 335 Sa/NU (Oliena, Sardinia). Beier’s description is not based on the female syntypes here examined, but almost certainly on a male, which has not been traced. In fact, the description is accompanied by the figures of a left chelicera ( Beier 1956b, fig. 1) (see above in Type material examined) and of a palp ( Beier 1956b, fig. 2) which is more slender than that of the female depicted here ( Figs 34–36 ) and has the same dimensions and ratios as those given in Beier’s description.

Following Beier (1956b), N. sardoum would have the movable cheliceral finger medially with a short, finely crenate, raised lamella or with a central simple and blunt tooth, but otherwise not toothed. Subsequently, this character has been considered differential between Ommatoblothrus species and those of the subgenus Neobisium ( Beier 1963; Heurtault 1979). The chelicera examined by Beier (1956b) probably had worn teeth, since in specimens of N. sardoum , and the other species examined here, the chelicerae have a movable finger with subequal teeth and a prominent tooth distal to seta gs.

Neobisium sardoum was compared by Beier (1956b) with N. henroti from Sardinia, and N. cerrutii from Latium, which were both transferred from the subgenus Blothrus to Ommatoblothrus . According to Beier (1956b), N. sardoum differs from N. henroti in having 6 setae at the posterior margin of carapace, greater number of tergal and sternal setae, slender pedipalpal hand, shorter chelal fingers, which are as long as the pedipalpal femur, more distal position of the trichobothrium ib and different ratio between basitarsus and telotarsus of leg IV.

The redescription of N. sardoum , based on many specimens which I believe are conspecific, all from Supramonte caves in eastern Sardinia, allows an evaluation of the morphological variability of this species and to better highlight its relationship with N. henroti , although of the latter only two females have been examined.

In the genus Neobisium the number of setae at the posterior margin of carapace is often the same as in tergite I, so N. sardoum has 6 setae (rarely 7) at the posterior margin of carapace and 7 setae (rarely 6) on tergite I: the standard number of setae at the posterior margin of carapace is presumably 6. The three known specimens of N. henroti have 4, 5 and 5 setae at the posterior margin of carapace, and 6, 6 and 5 setae, respectively, on tergite I: the standard number of setae in N. henroti cannot be established with certainty, as they could also be 6. The tergal and sternal chaetotaxy of the two species are not comparable, as the data provided by Beier in both descriptions (1956a, b) are not detailed and for N. henroti only those of females are known.

Neobisium sardoum has more slender palps than N. henroti [pedipalpal hand 2.48–3.06 (♂) or 2.50–2.60 (♀) times as long as broad in N. sardoum , 2.30 (♂) or 2.08–2.11 (♀) times as long as broad in N. henroti ] and different ratio between pedipalpal femur and chelal fingers [0.92–0.98 (♂) or 0.88–1.05 (♀) in N. sardoum , 0.83 (♂) or 0.81–0.82 (♀) in N. henroti ].

The relative position of the trichobothria along the chelal axis is not constant in N. sardoum ( Figs 38–41 ), however the most evident differences with N. henroti concern the positions of isb (the relative position is 0.84–0.87 in N. sardoum , 0.77–0.79 in N. henroti ), of ist (0.23–0.28 in N. sardoum , 0.33–0.42 in N. henroti ) and of st (0.27– 0.32 in N. sardoum , 0.24 in N. henroti ).

The ratio between basitarsus and telotarsus of leg IV appears to be different in the two species [0.75–0.92 (♂ ♀) in N. sardoum , 0.70–0.71 (♀) in N. henroti ], but it needs confirmation on the examination of further specimens of N. henroti .

The most important differential character between the two species, not mentioned by Beier (1956b), however concerns the pattern of dentition of fixed chelal finger: heterodentate in N. sardoum , but homodentate in N. henroti (see Remarks under N. henroti ).

The Neobisium (Neobisium) species with troglobitic facies present in Ligurian Alps and in central-southern Italy

Figures

FIGURE 118. Map depicting known distribution of Neobisum species with troglomorphic facies from Sardinia (A), Ligurian Alps and Corsica (B).

FIGURES 31–37. Neobisium (N.) sardoum Beier, 1956, male, Grotta Sa Nurra de Sas Palumbas, 10.V.1993 (Oliena, Sardinia). 31, epistome of carapace and right ocular area; 32, right chelicera, dorsal view; 33, anterior processes of right coxa I; 34, trochanter, femur and patella of right pedipalp, dorsal view; 35, right pedipalpal chela, dorsal view; 36, same, antiaxial view, with magnified details of teeth; 37, right leg IV, antiaxial view.

FIGURES 38–41. Neobisium (N.) sardoum Beier, 1956, position of trichobothria on chelal fingers. 38, male, Grotta del Portello (Urzulei, Sardinia); 39, male, Grotta Su Conti (Urzulei, Sardinia); 40, female, same; 41, female, Grotta Su Colostrargiu (Urzulei, Sardinia).

FIGURES 42–44. Neobisium (N.) sardoum Beier, 1956. 42, tritonymph, Grotta Su Palu, 27.V.1993 (Dorgali, Sardinia): epistome of carapace and left ocular area; 43, deutonymph, Grotta Nurra ‘e Pradu, 8.XI.2009 (Oliena, Sardinia): epistome of carapace and left ocular area; 44, same, detail of teeth at level of trichobothria et–it.