Neobisium (Neobisium) kozmaniense sp. nov. (Figs 2A–G)

urn:lsid:zoobank.org:act: F9475544-C67B-4540-97D9-5A1B70BBA548

Diagnosis (♂ ♀). A subterranean troglomorphic Neobisium from Georgia that differs from other Caucasian cave species of the genus in the following combination of characters: posterior margin of carapace with 6 setae, epistome triangular, anterior eyes with flattened lens, posterior eyes without lens, dark integument between anterior and posterior eyes present; tergites I–IV: 6:6:6–10:8–10; fixed and movable chelal fingers with 87–113 and 81–91 teeth, respectively; pedipalpal femur granulated, 1.14–1.47 mm length (× 5.17–5.91), patella 0.87–1.19 mm (× 2.95–3.88), movable finger 1.21–1.53 mm; ratio between movable chelal finger and hand of chela with pedicel 1.20–1.63; ratio between pedipalpal femur and movable chelal finger 0.81–1.21; ratio between pedipalpal femur and carapace 1.19–1.52.

Type material. Holotype: ♂, CaBOL-1036026: Georgia, Imereti Region, Zemo Imereti Plateou, Kozmani Cave (42°06’03.2”N 43°17’18.6”E), 960 m a.s.l., 27.11.2021, Eter Maghradze, Shalva Barjadze, Mariam Gogshelidze leg. Paratypes: 1♀, ISUIZ-044a; 1♀, ISUIZ-044b; 1♂, ISUIZ-044c: same locality as the holotype, 14.09.2021, Eter Maghradze leg; 1♀, CaBOL-1036025: same locality as the holotype, 27.11.2021, Eter Maghradze, Shalva Barjadze, Mariam Gogshelidze leg.

Derivatio nominis. The species name kozmaniense refers to the Kozmani Cave in Georgia, the type locality of the species.

Description of adults (♂ ♀). Carapace, chelicerae, pedipalps and palpal coxae red-brown, opisthosoma and legs yellowish; pedipalps smooth, with the exception of femur which is granulated; ophisthosoma with granular pleural membrane.

Carapace 1.13–1.29 (♂ ♀) times as long as broad, surface smooth, first pair of eyes with weak flattened lens, second pair just weak eyespots, cuticle pigmented darker between the eyes; anterior margin with long, pointed epistome, with a small base; carapace with 22 macrosetae (4:6:6:6) (Fig. 2A). Preocular microsetae absent.

Cheliceral palm with 6 (in one case 7) setae (Fig. 2B); fixed finger with 10–15 teeth, movable finger with 8–15 teeth, no big tooth in the middle; gs ratio 0.59–0.66, spinneret broad and rounded, in females more prominent; rallum with 8 blades, the distal two laterally pinnate; serrulae interior and exterior with about 26–38 and 28–34 blades, respectively.

Manducatory process with 5 setae. Coxal setae: pedipalp 6–10, I 5–7, II 6–9, III 6–8, IV 9–13; anterolateral process of coxa I strong triangular, anteromedial process weakly prominent with denticles (Fig. 2C).

Tergal chaetotaxy I–X (♂ ♀): 6:6:6–10:8–10:8–10:8–10:9–10:8–10:8–9:6–8. Sternal chaetotaxy II–X (♂): 8– 16:(2–3)12–18(2–3):(2–3)8–10(2–3):10:12:10–12:12:12:10–12; chaetotaxy of sternites II–X (♀): 10–18:(3–4)10– 16(3–4):(3)8–14(3):8–12:10–12:10–12:10–12:10–12:10–12. Anal cone with 2 ventral and 2 dorsal setae.

Pedipalp (Fig. 2D): trochanter 1.75–2.62 (♂ ♀) times as long as broad; femur 5.17–5.75 (♂) or 5.47–5.91 (♀) times as long as broad; patella 3.79–3.88 (♂) or 2.95–3.36 (♀) times as long as broad, base of chelal pedicel dorsally with 2–9 glandular pores; hand of chela reaching its greatest width in the proximal third in dorsal view; fixed chelal finger homodentate, with 87–113 (♂ ♀) pointed contiguous teeth; movable chelal finger with 81–91 (♂ ♀) low, flattened contiguous teeth (Fig. 2E), except in the distal third of the finger, where they are cuspidate; trichobothria as in fig. 2F, relative position of trichobothria along chelal axis (♂ ♀): it 0.15–0.21/ et 0.15–0.18/ est 0.21 –0.23/ ist 0.31– 0.42/ isb 0.69–0.75/ ib 0.78–0.92/ esb 0.92–0.94/ eb 0.93–0.95/ t 0.22–0.29/ st 0.37–0.40/ sb 0.63–0.68/ b 0.86–0.90.

Leg IV (Fig. 2G): trochanter 2.36–2.78 (♂) or 1.93–2.77 (♀) times as long as deep, femur + patella 3.67–3.89 (♂) or 3.09–3.80 (♀) times as long as deep, tibia 6.64–6.98 (♂) or 6.40–7.06 (♀) times, basitarsus 3.04–3.36 (♂) or 3.23–3.58 (♀) times, telotarsus 5.60–6.34 (♂) or 4.22–6.63 (♀) times as long as deep, ratio between basitarsus and telotarsus 0.55–0.83 (♂ ♀), subterminal seta bifurcate with serrated rami, claws with a very small dorsal tooth.

Ratio between movable finger and hand of chela with pedicel 1.20–1.63 (♂ ♀); ratio between pedipalpal femur and movable finger 0.81–1.21 (♂ ♀); ratio between pedipalpal femur and carapace 1.19–1.52 (♂ ♀).

Measurements (in mm). Body length 3.25–3.44 (♂) 2.97–4.13 (♀). Carapace 0.89–0.95 × 0.76–0.77 anteriorly (♂) or 0.93–1.05 × 0.72–0.89 anteriorly (♀). Chelicera 0.54–0.57 × 0.30–0.31 (♂) or 0.58–0.63 × 0.32–0.37 (♀); movable finger length 0.36 (♂) or 0.37–0.45 (♀). Pedipalp: trochanter 0.58–0.61 × 0.23–0.25 (♂) or 0.56–0.67 × 0.25–0.32 (♀); femur 1.14–1.35 × 0.22–0.24 (♂) or 1.36–1.47 × 0.24–0.27 (♀); patella 1.05–1.15 × 0.28–0.30 (♂) or 0.87–1.19 × 0.30–0.35 (♀); chela with pedicel 2.26–2.34 × 0.46–0.48 or 2.15–2.48 × 0.50–0.55 (♀); hand with pedicel length 0.86 (♂) or 0.93–1.13 (♀); movable finger length 1.40 (♂) or 1.21–1.53 (♀). Leg IV: trochanter 0.42–0.47 x 0.17–0.18 (♂) or 0.49–0.55 x 0.18–0.27 (♀); femur + patella 0.99–1.02 × 0.26–0.27 (♂) or 0.93–1.08 × 0.26–0.34 (♀); tibia 0.93–0.94 × 0.13–0.14 (♂) or 0.91–1.01 × 0.14–0.16 (♀); basitarsus 0.31–0.33 × 0.09–0.11 (♂) or 0.33–0.38 × 0.10–0.12 (♀); telotarsus 0.54–0.56 × 0.09–0.10 (♂) or 0.40–0.61 × 0.09–0.10 (♀).

Remarks. Neobisium kozmaniense sp. nov. differs from all other cave-dwelling species of the genus by its granulated pedipalpal tibia—the only exception is Neobisium sakadzhianum Krumpál, 1984, which also possess a granulated pedipalpal femur (Krumpál 1984). Neobisium kozmaniense sp. nov. differs from N. sakadzhianum in having a strong triangular epistome (small and almost flat epistome in N. sakadzhianum), pedipalpal femur 5.17– 5.91, patella 2.95–3.88 times longer than wide (pedipalpal femur is 9.23 times, patella 7.33 times longer, than wide in in N. sakadzhianum), tergites I–II each with 6 setae (each with 4 setae in in N. sakadzhianum) (Krumpál 1984). Neobisium sakadzhianum is known from Sakajia Cave which is a part of another karst massif (Sataplia-Tskaltubo karst massif, Imereti Region, Georgia), and the distance between the two cave entrances is about 45 km. Within the studied material, some degree of intraspecific variation was observed in case of several characters, especially in carapace, coxal, sternal and tergal chaetotaxy, in the relative position of chelal trichobothria, as well as in size and ratios. These are in line with the observations of Novák (2014) and Gardini (2023) on the intraspecific character variation of other cave dwelling Neobisium species.