Neobisium (Neobisium) magrinii, 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 : 35-36

Neobisium (Neobisium) magrinii n. sp.

( Figs 64–70 , 119 )

Type locality: Italy, Latium, Frosinone Province, Aurunci Mountains, Coreno Ausonio , Grotta l’Arnale 871 La /FR (41°20’55.45”N 13°45’42.30”E) .

Distribution. Italy: Latium.

Diagnosis (♂ ♀). A subterranean, troglomorphic Neobisium from Latium (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 convex lens, dark integument between anterior and posterior eyes absent; tergites I–IV: 4:4:4–6:4–6; cheliceral palm with 6 setae, rallum with 8–9 blades; fixed chelal finger homodentate, with contiguous teeth; fixed and movable chelal fingers with 145–166 and 124–150 teeth, respectively; pedipalpal femur 2.43–2.53 mm length (8.10–8.62 ×), patella 1.84–1.95 mm (5.70–6.10 ×), movable finger 2.64–2.85 mm; pedipalpal hand with long oval profile and its greatest width just proximally the middle; chelal fingers slightly curved both in dorsal and lateral view; ratio between movable chelal finger and hand of chela with pedicel 1.79–1.88; ratio between pedipalpal femur and movable chelal finger 0.87–0.92; ratio between pedipalpal femur and carapace 2.01–2.34; trichobothrium ist distal st or proximal st.

Type material. ITALY — Latium: Frosinone Province: 1 ♂ (holotype), Aurunci Mountains, Coreno Ausonio , Grotta l’Arnale 871 La /FR (41°20’55.45”N 13°45’42.30”E), 180 m a.s.l., 3.I.2000, L. Latella leg. ( MHNG). Paratypes: 1♂, same data as for holotype, 5.X.2008, P. Magrini leg. ; 2♀, id., 25.VII.2019, P. Magrini leg.

Derivatio nominis. Named in honour of Paolo Magrini (Florence), entomologist and biospeleologist, for his contribution to the knowledge of the Italian subterranean fauna.

Description of adults (♂ ♀). Carapace, chelicerae, pedipalps and palpal coxae red-brown; pedipalps smooth, pleural membrane granular. Carapace 1.35 (♂) or 1.32 (♀) times as long as broad, with four reduced eyes without tapetum ( Fig. 64 ), without dark integument between anterior and posterior eyes; anterior eyes with convex lens (diameter 0.09–0.11 mm), the posterior ones with a flatter lens; anterior margin of carapace with an equilateral triangular epistome ( Fig. 64 ); 18–19 macrosetae, anterior and posterior rows with 4 and 4 macrosetae, respectively, besides 1 preocular seta on each side. Chaetotaxy of tergites I–X: 4:4:4:4–5:6:6:6:6:7:7 (♂) or 4:4:4–6:6:5–6:6:6– 7:6–7:7:7 (♀). Chaetotaxy of sternites II–X: 13:(3)35(3):(2)12(2):12:12:12:12:10:10 (♂) or 12:(3)20(2):(2)10(2):12– 13:11–12:11–12:11–12:9–11:9–12 (♀); median genital sac not seen, genital atrium with 5+5 setae. Chelicera ( Fig. 65 ) 2.05 (♂) or 2.04–2.09 (♀) times as long as broad, palm with 6 setae (6 and 7 in a ♀); fixed finger with about 12 teeth (worn out), movable finger with about 9 teeth, one of which more prominent just proximal gs; gs ratio 0.65 (♂) or 0.61–0.64 (♀), spinneret prominent and broadly rounded in male ( Fig. 65 ), more prominent in female; rallum with 9 blades, the distal one laterally serrate-pinnate and isolated on a prominence, the second, the sixth and the seventh ones serrate, the others smooth, of decreasing length (♂), or with 8 blades, the proximal six smooth (♀); serrula exterior with about 35 blades. Manducatory process with 5 setae. Coxal setae: pedipalp 10–11, I 6–7, II 6–7, III 6, IV 10 (♂) or 8–11, I 5–8, II 6–8, III 6–7, IV 8–10 (♀); anterolateral process of coxa I squat and pointed, anteromedial process broadly rounded with denticles ( Fig. 66 ). Pedipalp ( Figs 67–69 ): trochanter 2.71 (♂) or 2.74– 2.87 (♀) times as long as broad, with 4 weak button-like tubercles (with lyrifissure) on antiaxial face; femur 8.43 (♂) or 8.10–8.62 (♀) times as long as broad, weakly enlarged distally; patella 6.10 (♂) or 5.70–5.84 (♀) times as long as broad, club gradually enlarged distally, ratio between club and pedicel 2.4 (♂) or 2.3–2.6 (♀), ratio X/Y = 0.25 (♂) or 0.25–0.29 (♀), base of pedicel dorsally with 4–6 glandular pores; chela with pedicel 7.81 (♂) or 7.50 (♀) times as long as broad; hand of chela with pedicel 2.81 (♂) or 2.77–2.78 (♀) times as long as broad, with long oval profile and its greatest width just proximally the middle; chelal fingers slightly curved both in dorsal and lateral view ( Figs 68–69 ); fixed chelal finger homodentate ( Fig. 69 ), with 166 (♂) or 145–159 (♀) contiguous teeth, nodus ramosus subterminal; movable chelal finger with 150 (♂) or 124–140 (♀) low, flattened contiguous teeth, apart from those distal the trichobothrium t, which are cuspidate ( Fig. 69 ); all teeth with dental canals; sensillum in variable position between trichobothria sb and st; trichobothria as in figs 68–69; relative position of trichobothria along chelal axis: it 0.10/ et 0.115/ est 0.155 / ist 0.31/ isb 0.80/ ib 0.91/ esb 0.965/ eb 0.975/ t 0.16/ st 0.36/ sb 0.71/ b 0.89 (♂); it 0.095 – 0.105 / et 0.115/ est 0.14 –0.155/ ist 0.31–0.335/ isb 0.81/ ib 0.92–0.93/ esb 0.97/ eb 0.98/ t 0.15/ st 0.28–0.41/ sb 0.67– 0.78/ b 0.91 (♀); trichobothrium est at level of t (♂ ♀); trichobothrium ist distal st or proximal st (♀); trichobothrium isb proximal sb (♂ ♀); ratio between movable finger and hand of chela with pedicel 1.88 (♂) or 1.79–1.82 (♀); ratio between pedipalpal femur and movable finger 0.90 (♂) or 0.87–0.92 (♀); ratio between pedipalpal femur and carapace 2.34 (♂) or 2.01–2.11 (♀). Leg IV ( Fig. 70 ): trochanter 2.88 (♂) or 2.65–2.96 times as long as deep, femur + patella 7.66 (♂) or 6.67–6.81 (♀) times as long as deep, tibia 13.35 (♂) or 11.57–13.03 (♀) times [TS = 0.36 (♂) or 0.225–0.29 (♀)], basitarsus 7.07 (♂) or 6.14–7.07 (♀) times [TS = 0.15 (♂) or 0.10–0.16 (♀)], telotarsus 11.45 (♂) or 10.33–11.56 (♀) times as long as deep [TS = 0.56 (♂) or 0.50 (♀)], ratio between basitarsus and telotarsus 0.73 (♂) or 0.69 (♀), subterminal seta dentate, not furcate ( Fig. 70 ), claws with small dorsal tooth.

Measurements. Body length 4.0 (♂) or 4.4–4.7 (♀). Carapace 1.08 (♂) or 1.15–1.24 (♀) × 0.80 (♂) or 0.87– 0.94 (♀) anteriorly. Chelicera 0.82 (♂) or 0.87–0.90 (♀) × 0.40 (♂) or 0.415–0.44 (♀); movable finger length 0.53 (♂) or 0.57–0.59 (♀). Pedipalp: trochanter 0.84 (♂) or 0.85–0.89 (♀) × 0.31 (♂) or 0.31 (♀); femur 2.53 (♂) or 2.43–2.50 (♀) × 0.30 (♂), 0.29–0.30 (♀); patella 1.95 (♂) or 1.84–1.88 (♀) × 0.32 (♂) or 0.315–0.33 (♀); chela with pedicel 4.14 (♂) or 3.98–4.20 (♀) × 0.53 (♂) or 0.53–0.56 (♀); hand with pedicel length 1.49 (♂) or 1.47–1.56 (♀); movable finger length 2.80 (♂) or 2.64–2.85 (♀). Leg IV: trochanter 0.78 (♂) or 0.72–0.73 (♀) × 0.27 (♂) or 0.26– 0.275(♀); femur + patella 2.30 (♂) or 2.18–2.27 (♀) × 0.30 (♂) or 0.32–0.34 (♀); tibia 2.07 (♂) or 1.91–2.02 (♀) × 0.155 (♂) or 0.155 –0.165 (♀); basitarsus 0.92 (♂) or 0.86–0.92 (♀) × 0.13 (♂) or 0.13–0.14 (♀); telotarsus 1.26 (♂) or 1.24–1.33 (♀) × 0.11 (♂) or 0.115–0.12 (♀).

Remarks. Neobisium magrinii n. sp., known only from the type locality is in the Aurunci Mountains, is morphologically very similar to N. patrizii from the Lepini Mountains, with which it shows the same high levels of troglomorphism. Neobisium magrinii differs from N. patrizii in having the anterior eyes with convex lens (anterior eyes with slightly convex lens or reduced to a white spot in N. patrizii ), the chelal hand with long oval profile and its greatest width just proximally the middle (chelal hand with its greatest width in the middle in N. patrizii ), the chelal fingers curved in lateral view (chelal fingers more straight in N. patrizii ), the fixed chelal finger always homodentate (homodentate or weakly heterodentate in N. patrizii ), the pedipalpal femur length 2.43–2.53 mm (2.07–2.41 mm in N. patrizii ), the movable chelal finger length 2.64–2.85 mm (2.36–2.50 mm in N. patrizii ) and the ratio between movable finger and hand of chela with pedicel 1.79–1.88 (1.66–1.82 in N. patrizii ).

Neobisium magrinii n. sp. shares the homodentate dentition of fixed chelal finger and the shape of pedipalpal chela with N. vignai n. sp., known from caves of the Ausoni and Aurunci Mountains, but it differs from N. vignai in having a more evident troglomorphism:for the main differential characters between the two species see Key to species.

Figures

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

FIGURES 64–70. Neobisium (N.) magrinii n. sp., male holotype, Grotta l’Arnale, 3.I.2000 (Coreno Ausonio, Latium). 64, epistome of carapace and right ocular area; 65, right chelicera, dorsal view; 66, anterior processes of left coxa I; 67, trochanter, femur and patella of right pedipalp, dorsal view; 68, right pedipalpal chela, dorsal view; 69, same, antiaxial view, with magnified detail of teeth; 70, right leg IV, antiaxial view, with magnified detail of subterminal seta of telotarsus.