Neobisium (Neobisium) vignai, Gardini, 2023

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 : 54-57

Neobisium (Neobisium) vignai n. sp.

( Figs 103–110 , 119 )

Neobisium (Ommatoblothrus) patrizii : Mahnert 1980: 23 (in part: Grotta dell’Aretino 611 La/LT).

Type locality: Italy, Latium, Frosinone Province, Ausoni Mountains, Amaseno , Grotta degli Ulivi 474 La /FR (41°27’20.65”N 13°17’20.99”E) .

Distribution. Italy: Latium.

Diagnosis (♂ ♀). A subterranean, troglomorphic Neobisium from Latium (Ausoni and Aurunci Mountains) that differs from other Mediterranean species of the genus in the following combination of characters: posterior margin of carapace with 4 setae, epistome triangular, anterior eyes with weak lens, dark integument between anterior and posterior eyes absent; tergites I–IV: 4–6:5–7:6–7:6–8; cheliceral palm with 6–7 setae, rallum with 8–9 blades; fixed chelal finger homodentate, with contiguous teeth; fixed and movable chelal fingers with 129–141 and 106–120 teeth, respectively; pedipalpal femur 1.79–2.14 mm length (6.63–7.34 ×), patella 1.33–1.61 mm (4.32–4.75 ×), movable finger 2.32–2.43 mm; pedipalpal hand with oval profile and its greatest width in the proximal third, chelal fingers slightly curved; ratio between movable chelal finger and hand of chela with pedicel 1.68–1.95; ratio between pedipalpal femur and movable chelal finger 0.77–0.88; ratio between pedipalpal femur and carapace 1.73–1.86; trichobothrium ist distal st or halfway between t and st.

Type material. ITALY — Latium: Frosinone Province: 1♀ (holotype), Ausoni Mountains, Amaseno , Grotta degli Ulivi 474 La /FR (41°27’20.65”N 13°17’20.99”E), 370 m a.s.l., 30.V.1992, L. Latella leg. ( MHNG). Paratypes: 4♀, same data as for holotype; 1♀, Ausoni Mountains , Amaseno, Risorgenza di Fontana Burano 602 La / FR (41°25’26”N 13°18’16.9”E), 510 m a.s.l., 21.VIII.2000, P. Magrini leg. Latium: Latina Province: 1♂, Ausoni Mountains, Prossedi , Pisterzo , Grotta dell’Aretino 611 La /LT (41°29’19.18”N 13°15’21.73”E), 30.XII.1992, L. Latella leg.

Non type material examined. ITALY — Latium: Frosinone Province: 1♀, Aurunci Mountains, Esperia , Grotta dei Serini 587 La /FR (41°20’52.20”N 13°38’34.66”E), VIII.2004, P. Magrini leg.

Derivatio nominis. The species is named for the late Augusto Vigna Taglianti (Borgo San Dalmazzo 25.VI.1943 – Rome 7.VI.2019), eclectic zoologist and naturalist, also in recognition of his contributions to the taxonomy, faunistics and biogeography of Mediterranean subterranean fauna.

Description of adults (♂ ♀) from type localities. Carapace, chelicerae, pedipalps and palpal coxae red-brown; pedipalps smooth, pleural membrane granular. Carapace 1.39 (♂) or 1.32 (♀) times as long as broad, with four reduced eyes without tapetum ( Fig. 103 ), without dark integument between anterior and posterior eyes; anterior eyes with a flat lens (diameter 0.08 mm), the posterior ones reduced to a white spot; anterior margin of carapace with a triangular epistome apically rounded ( Fig. 103 ); 20–22 macrosetae, anterior and posterior rows with 4 and 4 macrosetae, respectively, besides 1 preocular seta on each side (in fig. 103 only the insertion is present). Chaetotaxy of tergites I–X: 4:5:6:6:7:7:7:7:8:9 (♂) or 4–5:5–6:6–7:7:7–9:7–8:7–9:7–10:8–10:7–9 (♀). Chaetotaxy of sternites II–X: 11:(3)30(3):(3)10(3):10:10:10:10:10:10 (♂) or 8–9:(3)24–26(3):(3)9–12(3):12–13:10:10–13:11–12:10– 12:10–12 (♀); median genital sac and setae of genital atrium of male not seen. Chelicera ( Figs 104–105 ) 2.08 (♂) or 2.00–2.10 (♀) times as long as broad, palm with 6–7 setae (6 and 7 in female holotype); fixed finger (♂ ♀) with about 10–15 teeth, the 4–5 distal ones small and contiguous, the others erect and spaced; movable finger (♂ ♀) with 6–10 teeth, one of which more prominent just distal gs; gs ratio 0.60 (♂) or 0.64–0.66 (♀), spinneret slightly prominent and broadly rounded in male ( Fig. 105 ), more prominent, hemispherical in female ( Fig. 104 ); rallum with 8 blades (9 in female holotype), the distal one laterally serrate-pinnate and isolated on a prominence, the second one serrate, the others smooth and decreasing in length; serrulae interior and exterior with 28–30 and 34–35 blades, respectively. Manducatory process with 5 setae. Coxal setae: pedipalp 9–11, I 6–7, II 7–8, III 6–7, IV 11–12 (♂) or 10–12, I 6–8, II 6, III 6–7, IV 9–10 (♀); anterolateral process of coxa I squat and pointed, anteromedial process broadly rounded with denticles ( Fig. 106 ). Pedipalp ( Figs 107–109 ): trochanter 2.93 (♂) or 2.84–2.87 (♀) times as long as broad, with 2–3 weak button-like tubercles (with lyrifissure) on antiaxial face; femur 7.34 (♂) or 6.63–7.13 (♀) times as long as broad, weakly enlarged distally; patella 4.75 (♂) or 4.32–4.39 (♀) times as long as broad, club gradually enlarged distally, ratio between club and pedicel 2.3 (♂) or 1.9–2.2 (♀), ratio X/Y = 0.34 (♂) or 0.37–0.38 (♀), base of pedicel dorsally with 9 (♂) or 7–8 (♀) glandular pores; chela with pedicel 6.31 (♂) or 5.19–5.71 (♀) times as long as broad; hand of chela with pedicel 2.42 (♂) or 2.0–2.2 (♀) times as long as broad, with oval profile, a little globular, with its greatest width in the proximal third; chelal fingers slightly curved both in dorsal and lateral view ( Figs 108–109 ); fixed chelal finger homodentate ( Fig. 109 ), with 131 (♂) or 129–139 (♀) contiguous teeth, nodus ramosus subterminal; movable chelal finger with 120 (♂) or 106–112 (♀) low, flattened contiguous teeth, apart from those distal the trichobothrium t, which are cuspidate; all teeth with dental canals; sensillum (coupled sensilla?) closer to trichobothrium st than to sb (♂ ♀) or halfway between sb–st (♀ holotype); trichobothria as in figs 108–109; relative position of trichobothria along chelal axis: it 0.11/ et 0.14/ est 0.185 / ist 0.29/ isb 0.80/ ib 0.91/ esb 0.97/ eb 0.98/ t 0.18/ st 0.36/ sb 0.73/ b 0.91 (♂); it 0.12/ et 0.125–0.13/ est 0.17 –0.18/ ist 0.275–0.30/ isb 0.76–0.77/ ib 0.88–0.895/ esb 0.95–0.97/ eb 0.96–0.98/ t 0.17–0.19/ st 0.27–0.28/ sb 0.61–0.65/ b 0.86–0.89 (♀); trichobothrium est approximately at the level of t (♂ ♀); trichobothrium ist distal st (♂) or at level of st (♀); trichobothrium isb proximal sb (♂ ♀); ratio between movable finger and hand of chela with pedicel 1.68 (♂) or 1.70–1.76 (♀); ratio between pedipalpal femur and movable finger 0.87 (♂) or 0.83–0.88 (♀); ratio between pedipalpal femur and carapace 1.78 (♂) or 1.79–1.86 (♀). Leg IV ( Fig. 110 ): trochanter 2.87 (♂) or 2.86–2.94 (♀) times as long as deep, femur + patella 5.90 (♂) or 5.19–5.36 (♀) times as long as deep, tibia 9.45 (♂) or 9.33–10.18 (♀) times [TS = 0.38 (♂) or 0.31–0.38 (♀)], basitarsus 5.91 (♂) or 5.43–5.46 (♀) times [TS = 0.15 (♂) or 0.12–0.16 (♀)], telotarsus 10.63 (♂) or 8.78–9.43 (♀) times as long as deep [TS = 0.47 (♂) or 0.47–0.53 (♀)], ratio between basitarsus and telotarsus 0.70 (♂) or 0.70–0.76 (♀), subterminal seta furcate (♂) or dentate (♀) ( Fig. 110 ), claws with small dorsal tooth.

Measurements. Body length 4.3 (♂) or 4.7–5.0 (♀). Carapace 1.13 (♂) or 1.11–1.15 (♀) × 0.81 (♂) or 0.87 (♀) anteriorly. Chelicera 0.79 (♂) or 0.84–0.87 (♀) × 0.38 (♂) or 0.41–0.42 (♀); movable finger length 0.51 (♂) or 0.55 (♀). Pedipalp: trochanter 0.85 (♂) or 0.87–0.89 (♀) × 0.29 (♂) or 0.305–0.31 (♀); femur 2.02 (♂) or 1.99–2.14 (♀) × 0.275 (♂), 0.30 (♀); patella 1.52 (♂) or 1.49–1.61 (♀) × 0.32 (♂) or 0.345–0.37 (♀); chela with pedicel 3.60 (♂) or 3.54–3.62 (♀) × 0.57 (♂) or 0.62–0.69 (♀); hand with pedicel length 1.38 (♂) or 1.36–1.42 (♀); movable finger length 2.32 (♂) or 2.39–2.43 (♀). Leg IV: trochanter 0.69 (♂) or 0.73–0.735 (♀) × 0.24 (♂) or 0.25– 0.255(♀); femur + patella 1.77 (♂) or 1.77–1.79 (♀) × 0.30 (♂) or 0.33–0.345 (♀); tibia 1.56 (♂) or 1.54–1.68 (♀) × 0.165 (♂ ♀); basitarsus 0.71 (♂) or 0.71–0.76 (♀) × 0.12 (♂) or 0.13–0.14 (♀); telotarsus 1.01 (♂) or 0.99–1.01 (♀) × 0.095 (♂) or 0.105 –0.115 (♀).

Description of adult (♀) from Aurunci Mountains: Grotta dei Serini 587 La/FR. (Characters as in type specimens are omitted). Carapace 1.32 times as long as broad, with four very reduced eyes; anterior margin of carapace with an equilateral triangular epistome; 20 macrosetae, anterior and posterior rows with 4 and 4 macrosetae, respectively, besides 1 preocular seta on each side. Chaetotaxy of tergites I–X: 6:7:7:8:8:8:8:9:9:9. Chaetotaxy of sternites II–X: 7:(3)22(3):(3)13(3):12:13:13:11:12:11. Chelicera 2.02 times as long as broad, palm with 6 and 7 setae; fixed finger with about 12 teeth, movable finger with a prominent tooth just distal gs; gs ratio 0.63, spinneret prominent and hemispherical; rallum with 8 blades, the distal one laterally serrate-pinnate and isolated on a prominence, the second one serrate, the others smooth and decreasing in length. Manducatory process with 5 setae. Coxal setae: pedipalp 12, I 6–8, II 7–8, III 5–6, IV 9–10. Pedipalp: trochanter 2.72 times as long as broad; femur 6.88 times as long as broad, weakly enlarged distally; patella 4.43 times as long as broad, club gradually enlarged distally, ratio between club and pedicel 1.8, ratio X/Y = 0.39; chela with pedicel 5.94 times as long as broad; hand of chela with pedicel 2.12 times as long as broad, with oval profile and its greatest width in the proximal third (dorsal view); chelal fingers slightly curved both in dorsal and lateral view; fixed chelal finger homodentate, with 141 contiguous teeth; movable chelal finger with 112 low, flattened contiguous teeth, apart from those distal the trichobothrium t, which are cuspidate; sensillum closer to trichobothrium st than to sb; relative position of trichobothria along chelal axis: it 0.12/ et 0.14/ est 0.19 / ist 0.275/ isb 0.82/ ib 0.89/ esb 0.95/ eb 0.97/ t 0.18/ st 0.355/ sb 0.75/ b 0.89; trichobothrium est approximately at the level of t; trichobothrium ist halfway between t and st; trichobothrium isb proximal sb; ratio between movable finger and hand of chela with pedicel 1.95; ratio between pedipalpal femur and movable finger 0.77; ratio between pedipalpal femur and carapace 1.73. Leg IV: trochanter 2.58 times as long as deep, femur + patella 6.11 times as long as deep, tibia 10.0 times (TS = 0.33), basitarsus 5.75 times (TS = 0.10), telotarsus 9.14 times as long as deep (TS = 0.52), ratio between basitarsus and telotarsus 0.72, subterminal seta furcate, claws with small dorsal tooth.

Measurements. Body length 4.0. Carapace 1.03 × 0.78 anteriorly. Chelicera 0.77 × 0.38; movable finger length 0.48. Pedipalp: trochanter 0.79 × 0.29; femur 1.79 × 0.26; patella 1.33 × 0.30; chela with pedicel 3.33 × 0.56; hand with pedicel length 1.19; movable finger length 2.32. Leg IV: trochanter 0.62 × 0.24; femur + patella 1.65 × 0.27; tibia 1.45 × 0.145; basitarsus 0.69 × 0.12; telotarsus 0.96 × 0.105.

Remarks. The disjunct population from the cave Grotta dei Serini 587 La/FR near Esperia, in the Aurunci Mountains―of which only one female was examined―is attributed to N. vignai n. sp. as the only differences found with the specimens from the Ausoni Mountains are a slightly smaller size (pedipalpal femur length 1.79 mm versus 1.99–2.14 mm, pedipalpal patella length 1.33 mm versus 1.49–1.56 mm, pedipalpal chela length 3.33 mm versus 3.54–3.60 mm) and the presence of 6 setae on tergite I versus 4 (rarely 5) setae in specimens from Ausoni Mountains. On the presumed conspecificity of the specimen from Aurunci Mountains attributed to N. vignai n. sp., see Remarks under N. leolatellai n. sp.

The affinities of N. vignai n. sp. are uncertain.Among the species from mainland Italy presenting an homodentate pedipalpal fixed finger, it could be related to N. magrinii from the Aurunci Mountains, this latter with a higher adaptive specialization than N. vignai (see Key to species).

Neobisium vignai n. sp. is similar to N. sp. aff. patrizii from the Lepini Mountains, with which it shares the same degree of adaptive morphological features (that is, size and slenderness of the appendages), the chaetotaxy of carapace, of tergites I–IV and of cheliceral palm. The main differences between the two species concern the dentition of the fixed pedipalpal finger (homodentate in N. vignai , heterodentate in N. sp. aff. patrizii ) and the shape of the chelal hand, slightly more globular in N. vignai (2.00-2.42 times as long as broad), more tapered in N. sp. aff. patrizii (1.94-2.74 times as long as broad).

Figures

FIGURE 119. Map depicting known distribution of Neobisum species with troglomorphic facies from central and southern Italy.

FIGURES 103–110. Neobisium (N.) vignai n. sp., female holotype, Grotta degli Ulivi (Amaseno, Latium) (unless otherwise stated). 103, epistome of carapace and right ocular area; 104, right chelicera, dorsal view; 105, male paratype, Grotta dell’Aretino (Prossedi, Latium): movable finger of right chelicera, dorsal view; 106, anterior processes of left coxa I; 107, trochanter, femur and patella of right pedipalp, dorsal view; 108, right pedipalpal chela, dorsal view; 109, same, antiaxial view, with magnified detail of teeth; 110, right leg IV, antiaxial view, with magnified detail of subterminal seta of telotarsus.