Bisetocreagris brevis, Feng & Zhang & Chen, 2023

Feng, Zegang, Zhang, Feng & Chen, Jun, 2023, Cave-dwelling Neobisiidae in South China Karst, with descriptions of twelve new species of Bisetocreagris (Pseudoscorpiones, Neobisiidae) from Guizhou Province, Zootaxa 5395 (1), pp. 1-77 : 16-22

Bisetocreagris brevis sp. nov. (Ħae双ŁÞ伪AE)

http://zoobank.org:act: 2264FA33-7C38-4EBB-8A1C-E60AC84B3F23

Figs 12–16

Type material. Holotype male (Ps.- MHBU-GZ20082201 ): China, Guizhou Province, Tongren City, Yinjiang County, Chanxi Town, Zhoujiaao Village, Yehu Cave (âṅåȇ仁Ṅ印ũ县dzäDz周ẋ坳ť夜壶ñ), [27°51.113′N, 108°30.593′E], 982 m a.s.l., 22 August 2020, Zegang Feng, Hongru Xu, Yanmeng Hou leg.

Paratypes: 3 males (Ps.- MHBU-GZ20082202‒04 ) , 6 females (Ps.- MHBU-GZ20082205‒10 ), same data as the holotype ; 1 female (Ps.- MHBU-GZ14102101 ), same location as holotype, 21 October 2014, Xuankong Jiang leg.

Etymology. The species name is derived from the Latin word “ brevis ”, meaning short and little, and refers to the shape of the pedicel of the pedipalp hand.

Distribution. This new species is known only from the type locality Yehu Cave ( Figs 1D , 12 ), located about ~ 4.5 km to the east of Chanxi Town, Tongren City. The entrance is irregular oval (~ 1.5 m high and ~ 4 m wide), sheltered in a forest about 15 m below the man-made diversion canal and surrounded by weeds. The cave is moist, about 100 m long, extending horizontally. All specimens were collected on the wall ( Fig. 12D ) of the dark zone.

Diagnosis. (♂ ♀). Troglomorphic habitus; carapace without eyes or eyespots; epistome triangular, with rounded tip; carapace with 4–6 setae on posterior margin; pedipalp smooth and slender, both chelal fingers with 120–139 teeth; femur 8.14–8.81 times (length 2.19–2.44), patella 6.84–7.40 times (length 2.05–2.27) longer than wide, pedicel about one-third of the total length of patella. Hand with pedicel 3.00–3.42 times (length 1.54–1.72), chela with pedicel 7.69–8.02 (♂), 7.13–7.79 (♀) times (length 3.61–3.92) longer than wide, finger 1.41–1.52 times longer than hand with pedicel. Chelicera: rallum with 10–14 pinnate setae, distal one with a slightly expanded base, distal-most 1–3 blades slightly separated from others, proximal one short.

Description. Male (holotype; paratypes males in parentheses; Figs 13 , 14A ). Carapace, chelicerae, and pedipalps reddish brown; abdomen and legs yellowish.

Carapace ( Figs 15A–B , 16A ): smooth, 1.18 (1.17–1.23) times longer than wide, with a total of 27 (24–26) setae, including 4 (3–4) on anterior margin, 6 (4–4) on posterior margin, and 2–3 (2–3) on each side of antero-lateral margin; without eyes or eyespots ( Fig 15B ); epistome triangular, with rounded tip.

Chelicera ( Figs 15C , 16B–D, F ): hand with 6 (6–7) setae, movable finger with 1 (1) submedial seta; fixed finger with 14–15 (13–19) teeth; movable finger with 12–14 (13–16) teeth; serrula exterior with 35 (33) lamellae; serrula interior with 25 (23) lamellae. Galea ( Figs 16D, F ) elongated with only one main branch, apically forked. Rallum ( Fig. 16C ) with 11 (10–14) pinnate blade, distal-most blade with a slightly expanded base, distal-most 1–2 blades slightly separated from others, proximal one short.

Pedipalps ( Figs 15D–E , 16I–K ): apex of coxae rounded, with 5 (5) setae on each side, pedipalpal coxae with 6 (6–8) setae. Pedipalp slender and smooth. Trochanter 3.26 (3.20–3.32) times longer than wide, femur 8.36 (8.42– 8.70), patella 7.28 (6.84–7.40) times longer than wide, pedicel about one-third of the total length of patella, chela (with pedicel) 7.98 (7.69–8.02), chela (without pedicel) 7.59 (7.24–7.60) times longer than wide, movable finger 1.61 (1.64–1.72) times longer than hand (without pedicel). Fixed chelal finger with 8 trichobothria, movable finger with 4, eb and esb on lateral margin of hand; ib, ist and isb closely grouped at the base of the fixed finger; est proximal of finger middle; it -et at same level near fingertip; on movable finger st nearer to t than to sb, the latter nearer b than to st, the distance between sb and b is somewhat equal to that of st and t ( Figs 15D , 16I–J ). Venom apparatus present only in fixed chelal finger, venom duct short, not extending past half of the distance to et. Fixed chelal finger with 127 (131–139) pointed and retrorse teeth; movable finger with 128 (129–134) teeth, which are pointed and retrorse in distal, blunt and round in middle and basal part; all teeth contiguous.

Abdomen: pleural membrane granulated. Tergal chaetotaxy (I–XI): 6:6:6:6:6:6:6:6:8:7:8 (5–6:3–6:6:6:6:5– 6:6:6–7:6–8:6–8:7);sternal chaetotaxy(V–XI):10:15:14:13:12:13:13:4(10–12:11–14:11–13:12:12–13:12–14:12:4); stigmata with 5–6 (3–7) setae; anal cone with 2 (2) dorsal and 2 (2) ventral setae. Male genital area ( Figs 15F , 16G ): sternite II with 42 (39–44) scattered setae; sternite III with anteromedian groove flanked by one small seta on each side, with 31 (27–34) posterior setae.

Legs: coxae chaetotaxy (I–IV): 9:7:4:8–9 (7–11:6–9:3–5:8–10). Leg I ( Figs 15H , 16L ): femur 7.05 (6.38– 7.17), patella 4.94 (4.53–4.94), tibia 8.54 (8.15–9.38), basitarsus 5.27 (5.09–5.64), telotarsus 7.00 (7.27–7.50) times longer than wide, femur 1.60 (1.54–1.68) times longer than patella, telotarsus 1.33 (1.27–1.34) times longer than basitarsus.

Leg IV ( Figs 15I , 16E, M ): femur + patella 8.36 (7.96–8.58) times longer than wide, femur shorter than patella, tibia 11.76 (11.76–12.80), basitarsus 5.77 (5.20–5.54), telotarsus 7.25 (7.31–8.27) times longer than wide, telotarsus 1.16 (1.19–1.26) times longer than basitarsus; basitarsus with one tactile setae (TS=0.13–0.14), telotarsus with one tactile setae (TS=0.59–0.62); subterminal tarsal seta ( Fig. 16E ) bifurcated, both branches dentate; arolium not divided, shorter than the slender and simple claws.

Females (paratypes; Fig. 14B ): mostly same as holotype and paratypes males.

Chelicera. Hand with 6–7 setae, movable finger with 1 submedial seta; fixed finger with 14–18 teeth; movable finger with 12–16 teeth; serrula exterior with 35–38 lamellae; serrula interior with 27–34 lamellae. Galea with only one main branch and apically forked; rallum of 11–14 blades, and similar to holotype.

Pedipalps. Apex of coxae rounded, with 5 setae on each side. Pedipalpal coxae with 5–8 setae. Trochanter 3.13–3.28, femur 8.14–8.81, patella 6.84–7.40, chela (with pedicel) 7.13–7.79, chela (without pedicel) 6.70–7.35 times longer than wide, movable finger 1.58–1.65 times longer than hand (without pedicel). Fixed chelal finger with about 121–137 teeth, movable finger with about 120–135 teeth.

Abdomen. Tergal chaetotaxy (I–XI): 5–6:3–6:5–6:4–6:6:5–7:6–7:6–7:6–8:7–8:7–8; sternal chaetotaxy (IV– XI): 9–12:12–15:12–16:12–13:12–14:11–14:12–13:2–4. Female genital area ( Figs 15G , 16H ): sternite II with 4–9 setae on each side; sternite III with a row of 16–21 setae on the posterior margin.

Measurements: (length/breadth or depth in mm; ratios for most characters in parentheses). Holotype male (paratypes males in square brackets). Body length 4.52 [4.73–5.02]. Carapace 1.13/0.96 (1.18) [1.04–1.16/0.89– 0.96 (1.17–1.23)]. Pedipalpal trochanter 1.01/0.31 (3.26) [0.96–1.03/0.30–0.32 (3.20–3.32)], femur 2.34/0.28 (8.36) [2.19–2.38/0.26–0.28 (8.42–8.70)], patella 2.11/0.29 (7.28) [2.05–2.22/0.29–0.31 (6.84–7.40)], chela (with pedicel) 3.67/0.46 (7.98) [3.61–3.88/0.45–0.49 (7.69–8.02)], chela (without pedicel) 3.49/0.46 (7.59) [3.42–3.67/0.45–0.49 (7.24–7.60)], hand length (without pedicel) 1.38 [1.37–1.44], movable finger length 2.22 (1.61 times longer than hand without pedicel) [2.24–2.41 (1.64–1.72 times longer than hand without pedicel)]. Leg I: trochanter 0.39/0.23 (1.70) [0.37–0.40/0.22–0.25 (1.60–1.68)], femur 1.34/0.19 (7.05) [1.29–1.37/0.18–0.21 (6.38–7.17)], patella 0.84/0.17 (4.94) [0.77–0.89/0.17–0.18 (4.53–4.94)], tibia 1.11/0.13 (8.54) [1.06–1.22/0.13 (8.15–9.38)], basitarsus 0.58/0.11 (5.27) [0.56–0.63/0.11–0.12 (5.09–5.64)], telotarsus 0.77/0.11 (7.00) [0.75–0.80/0.10–0.11 (7.27–7.50)]. Leg IV: trochanter 0.63/0.25 (2.52) [0.57–0.68/0.22–0.27 (2.52–2.62)], femur + patella 2.09/0.25 (8.36) [2.05– 2.23/0.24–0.27 (7.96–8.58)], tibia 2.00/0.17 (11.76) [1.92–2.07/0.15–0.17 (11.76–12.80)], basitarsus 0.75/0.13 (5.77) [0.72–0.78/0.13–0.15 (5.20–5.54)], telotarsus 0.87/0.12 (7.25) [0.91–0.95/0.11–0.13 (7.31–8.27)].

Females (paratypes). Body length 3.41–5.53. Carapace 1.15–1.19/0.91–1.07 (1.11–1.29). Pedipalpal trochanter 1.00–1.09/0.32–0.34 (3.13–3.28), femur 2.25–2.44/0.27–0.29 (8.14–8.81), patella 2.15–2.27/0.30–0.32 (6.84–7.40), chela (with pedicel) 3.68–3.92/0.48–0.53 (7.13–7.79), chela (without pedicel) 3.48–3.68/0.48–0.53 (6.70–7.35), hand length (without pedicel) 1.41–1.52, movable finger length 2.28–2.49 (1.58–1.65 times longer than hand without pedicel). Leg I: trochanter 0.37–0.44/0.24–0.26 (1.54–1.69), femur 1.33–1.41/0.20–0.22 (6.32–7.00), patella 0.82– 0.90/0.17–0.19 (4.32–4.94), tibia 1.11–1.21/0.13–0.14 (8.54–9.00), basitarsus 0.57–0.63/0.11–0.13 (4.46–5.73), telotarsus 0.74–0.82/0.11–0.12 (6.17–7.45). Leg IV: trochanter 0.65–0.71/0.25–0.28 (2.54–2.65), femur + patella 2.12–2.27/0.25–0.29 (7.31–8.88), tibia 1.95–2.11/0.17–0.20 (10.30–11.72), basitarsus 0.75–0.80/0.14–0.16 (4.69– 5.71), telotarsus 0.90–0.99/0.12–0.15 (6.20–8.00).

Remarks. Bisetocreagris brevis sp. nov. resembles B. juanxuae Mahnert et Li, 2016 , B. scaura ( Mahnert, 2003) and B. titania ( Mahnert, 2003) in having a similar slender pedipalpal and the pedipalpal pedicel that is about half the entire length of pedipalpal patella. The new species differs from B. juanxuae by the absence of eyes or eyespots (vs. B. juanxuae with 2 indistinct small eyes), the pedipalpal patella 6.84–7.40 (♂ ♀) times longer than wide (vs. 9.6 (♂), 9.1(♀) times in B. juanxuae ), the chela (with pedicel) 7.69–8.02 (♂), 7.13–7.79 (♀) times longer than wide (vs. 10.8 (♂), 10.0 (♀) times in B. juanxuae ); and the presence of 127–139 teeth on both chelal fingers (vs. 146‒152 teeth in B. juanxuae ).

Bisetocreagris brevis sp. nov. differs from B. scaura by the pedipalpal femur 8.36–8.70 (♂), 8.14–8.81 (♀) times longer than wide (vs. 7.52 (tritonymph) times in B. scaura ), the chela (with pedicel) 7.69–8.02 (♂), 7.13–7.79 (♀) times longer than wide (vs. 8.65 (tritonymph) times in B. scaura ), and the presence of 127–139 teeth on both chelal fingers (vs. 105 teeth in B. scaura ).

This new species differs from B. titania by the pedipalpal femur 8.36–8.70 (♂) times longer than wide (vs. 8.9 (♂) times in B. titania ), the patella 6.84–7.40 (♂) times longer than wide (vs. 8.0 (♂) times in B. titania ), and the presence of 127–139 teeth on both chelal finger (vs. 103‒110 teeth in B. titania ).

Figures

FIGURE 1. Distribution map of the type locality of troglomorphic Bisetocreagris species in China. A. B. maomaotou Gao, Wynne et Zhang, 2018 (Maomaotou Cave); B. B. que sp. nov. (Yanggong Cave); C. B. longidigitata sp. nov. (Mao’er Cave); D. B. brevis sp. nov. (Yehu Cave); E. B. aspera sp. nov. (Tu Cave); F. B. jiangi sp. nov. (Anjialin Cave); G. B. tenuipalma sp. nov. (Sanjie Cave); H. B. changbing sp. nov. (Sanyuan and Guanyin caves); I. B. ampla sp. nov. (Hei Cave); J. B. gracilenta Gao et Zhang, 2017 (Shanmu Cave); K. B. guangshanensis Gao et Zhang, 2017 (Guangshan Cave); L. B. chumi sp. nov. (Tufei Cave); M. B. sanmen sp. nov. (Sanmen Cave); N. B. xishui sp. nov. (Dongkoushang Cave); O. B. baozinensis Mahnert et Li, 2016 (Baozi Cave); P. B. chuanensis Mahnert et Li, 2016 (Chuan Cave); Q. B. grandis sp. nov. (Wulibeidadong Cave); R. B. scaura (Mahnert, 2003) (Dahei Cave); S. B. martii (Mahnert, 2003) and B. titania (Mahnert, 2003) (Guoquan Cave); T. B. xiaoensis Li et Liu, 2017 (Xiao Cave); U. B. juanxuae Mahnert et Li, 2016 (Dao Cave); V. B. cavernarum Mahnert et Li, 2016 (Ert Long Cave); W. B. chinacavernicola (Schawaller, 1995) (Xian Nin and Chao-Tian caves).

FIGURE 12. Yehu Cave, type locality of Bisetocreagris brevis sp. nov., A. Surrounding surface vegetation with cave entrance; B‒C. Entrances (B: Outside the entrance; C: Inside the entrance); D. Area where B. brevis sp. nov. specimens were collected.

FIGURE 13. Live individual of Bisetocreagris brevis sp. nov. (male) on the wall.

FIGURE 14. Bisetocreagris brevis sp. nov., A. Holotype male, dorsal view; B. Paratype female, dorsal view.

FIGURE 15. Bisetocreagris brevis sp. nov., holotype male (A–F, H–I), female (G). A. Carapace, dorsal view; B. Eye area, lateral view; C. Right chelicera, dorsal view; D. Right chela, lateral view; E. Right pedipalp, dorsal view; F. Male genitalia; G. Female genitalia; H. Right leg I, lateral view; I. Right leg IV, lateral view.

FIGURE 16. Bisetocreagris brevis sp. nov., holotype male (A–G, I–M), female (H). A. Carapace, dorsal view; B. Right chelicera, dorsal view; C. Rallum; D. Movable finger of chelicera, showing galea; E. Subterminal tarsal seta; F. Galea; G. Male genitalia, ventral view; H. Female genitalia, ventral view; I. Right chela, dorsal view; J. Right chelal fingers, retrolateral view; K. Right pedipalp, minus chela, dorsal view; L. Right leg I, lateral view; M. Right leg IV, lateral view. Scale bars: 0.1 mm (C–E), 0.25 mm (B, G–H), 0.5 mm (A, J), 1 mm (I, K–M).