Bisetocreagris tenuipalma, 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 : 62-68

Bisetocreagris tenuipalma sp. nov. (āậ双ŁÞ伪AE)

http://zoobank.org:act: 403FE985-07FA-4FCC-8FE9-F40EAC6476DC

Figs 52–56

Type material. Holotype male (Ps.- MHBU-GZ19072601 ): China, Guizhou Province, Zunyi City, Fenggang County, Heba Town, Sanjie Cave (âṅåǎ义Ṅ凤冈县ª坝Dz三ḃñ), [27°54′16.26″N, 107°47′53.44″E], 1859 m a.s.l., 26 July 2019, Zegang Feng & Chen Zhang leg.

Paratypes: 5 males (Ps. -MHBU-GZ19072602‒06 ) , 7 females (Ps. -MHBU-GZ19072607‒13 ), same data as the holotype .

Etymology. The specific name is derived from a combination of the Latin word “ tenuis ” and “ palma ”, meaning thin and palm, respectively, and referring to the shape of the pedipalp hand.

Distribution and habitat. This new species is known only from the type locality Sanjie Cave ( Figs 1G , 52 ), located ~ 8 km east of Heba Town, Fenggang County. The entrance of the cave is located in a karst sinkhole covered by a large number of bushes and surrounded by farmland. The entrance is an approximate rectangular crack (5 m high and 20 m wide), which extends obliquely downward to a drainage pit. Specimens were collected on the wall ( Figs 52C–D ) in the rock cracks from the dark zone.

Diagnosis. (♂ ♀). Troglomorphic habitus; carapace with 4 eyespots on the slightly raised surface; epistome small and triangular; carapace with 6–7 setae on posterior margin; pedipalp smooth and slender except for hand which is finely granular; both chelal fingers with 157–192 teeth, femur 7.86–8.59 (♂), 7.44–8.28 (♀) times (length 2.28–2.75 (♂), 2.30–2.56 (♀ )) longer than wide, patella 7.44–8.13 (♂), 6.81–7.59 (♀) times (length 2.40–2.87) longer than wide, pedicel about half the entire length of patella. Hand with pedicel 3.46–3.81 (♂), 3.15–3.54 (♀) times (length 1.56–1.83 (♂) longer than wide, 1.60–1.81 (♀ )), chela with pedicel 8.37–9.17 (♂), 7.31–8.35 (♀) times (length 3.83–4.40 (♂), 3.88–4.23 (♀ )) longer than wide, finger 1.50–1.61 (♂), 1.46–1.58 (♀) times longer than hand with pedicel. Chelicera: rallum with 8 pinnate setae, distal one with an expanded base.

Description. Male (holotyape; paratypes males in parentheses; Figs 53A , 54A ). Carapace, chelicerae, and pedipalps yellowish brown; abdomen and legs yellowish.

Carapace ( Figs 55A , 56A–B ): smooth, 1.21 (1.20–1.29) times longer than wide, with a total of 24 (24–27) setae, including 4 on anterior margin, 6 (6–7) on posterior margin, and 1 (1–3) on each side of antero-lateral margin; with 4 eyespots on the slightly raised surface ( Fig. 55B ); epistome small and triangular.

Chelicera ( Figs 55C , 56B–C, E ): hand with 6–7 setae, movable finger with 1 submedial seta; fixed finger with 12–15 (12–16) teeth; movable finger with 12–14 (12–16) teeth; serrula exterior with 34–38 lamellae; serrula interior with 27–28 lamellae. Galea ( Fig. 56E ) divided into 2 main branches and apically forked. Rallum ( Fig. 56C ) with 8 pinnate blades, distal-most blade with slightly expanded base, distal-most 2–3 blades separated from others, proximal one short.

Pedipalps ( Figs 55D–E , 56I–K ): apex of coxae rounded, with 3–5 (4–5) setae on each side, pedipalpal coxae with 6 (6–9) setae. Pedipalp smooth and slender except for hand, which is finely granular. Trochanter 3.61 (3.22– 3.73) times longer than wide, femur 8.03 (7.86–8.59), patella 7.44 (7.50–8.13) times longer than wide, pedicel about half the entire length of patella, chela (with pedicel) 8.80 (8.37–9.17), chela (without pedicel) 8.07 (7.76–8.46) times longer than wide, movable finger 1.88 (1.80–1.96) 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 slightly distal of finger middle; it slightly closer to fingertip than et; on movable finger st nearer to t than to sb, the latter nearer b than to st, the distance between sb and b longer than that of st between t ( Figs 55D , 56I–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 168 (157–190) teeth, which are flat and retrorse in distal and middle part, blunt and rounded in basal part; movable finger with 173 (158–192) teeth, which are flat and retrorse in distal part, blunt and rounded in middle and basal part; all teeth contiguous.

Abdomen: pleural membrane granulated. Tergal chaetotaxy (I–XI): 7:5:6:6:6:6:6:8:9:9:6 (6–7:6–8:6–7:6:6–7:6– 8:7–8:7–10:8–10:9–10:6–8); sternal chaetotaxy (V–XI):10:15:12:15:15:14:12:4 (8–10:14–17:14–16:13–16:13– 16:13–17:12–14:3–4); stigmata with 5–6 (5–8) setae; anal cone with 2 dorsal and 2 ventral setae. Male genital area ( Figs 55F , 56G ): sternite II with 40 (35–47) scattered setae; sternite III with anteromedian groove flanked by one small seta on each side, with 18 (14–19) posterior setae.

Legs: coxae chaetotaxy (I–IV): 8:7–8:3–5:10 (8–12:7–11:4–6:10–14). Leg I ( Figs 55H , 56L ): femur 8.22 (7.19– 7.68), patella 5.18 (4.50–5.11), tibia 8.64 (8.36–10.00), basitarsus 5.64 (4.77–5.91), telotarsus 6.08 (6.00–7.25) times longer than wide, femur 1.68 (1.70–1.88) times longer than patella, telotarsus 1.18 (1.20–1.32) times longer than basitarsus.

Leg IV ( Figs 55I , 56F, M ): femur + patella 8.48 (7.06–8.56) times longer than wide, femur shorter than patella, tibia 11.47 (10.90–12.35), basitarsus 5.71 (5.14–6.13), telotarsus 7.07 (6.53–8.07) times longer than wide, telotarsus 1.24 (1.21–1.32) times longer than basitarsus; basitarsus with one tactile seta (TS=0.10–0.14), telotarsus with one tactile seta (TS=0.58); subterminal tarsal seta ( Fig. 56F ) bifurcate, both branches dentate; arolium not divided, shorter than the slender and simple claws.

Females (paratypes; Figs 53B , 54B ): similar to holotype and paratypes males.

Chelicera. Hand with 6–7 setae, movable finger with 1 submedial seta; fixed finger with 12–18 teeth; movable finger with 12–18 teeth; serrula exterior with 36–41 lamellae; serrula interior with 28–30 lamellae. Galea divided into 2 main branches and apically forked; rallum of 8 blades, and similar to holotype.

Pedipalps. Apex of coxae rounded, with 3–5 setae on each side. Pedipalpal coxae with 6–9 setae. Trochanter 3.18–3.50, femur 7.44–8.28, patella 6.81–7.59, chela (with pedicel) 7.31–8.35, chela (without pedicel) 6.72–7.69 times longer than wide, movable finger 1.77–1.95 times longer than hand (without pedicel). Fixed chelal finger with about 163–172 teeth, movable finger with about 165–173 teeth.

Abdomen. Tergal chaetotaxy (I–XI): 6–8:5–6:5–6:5–6:6–7:7–9:8–9:8–10:9–10:9–11:6–8; sternal chaetotaxy (IV–XI): 6–10:13–16:13–16:14–16:15–16:14–17:13–15:4. Female genital area ( Figs 55G , 56H ): sternite II with 2–5 setae on each side; sternite III with a row of 12–17 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 3.85 [2.99–4.03]. Carapace 1.25/1.03 (1.21) [1.15–1.29/0.92– 1.03 (1.20–1.29)]. Pedipalpal trochanter 1.12/0.31 (3.61) [1.02–1.23/0.30–0.33 (3.22–3.73)], femur 2.49/0.31 (8.03) [2.28–2.75/0.28–0.32 (7.86–8.59)], patella 2.53/0.34 (7.44) [2.40–2.87/0.30–0.36 (7.50–8.13)], chela (with pedicel) 4.05/0.46 (8.80) [3.83–4.40/0.45–0.48 (8.37–9.17)], chela (without pedicel) 3.71/0.46 (8.07) [3.54–4.06/0.45–0.48 (7.76–8.46)], hand length (without pedicel) 1.39 [1.28–1.49], movable finger length 2.61 (1.88 times longer than hand without pedicel) [2.44–2.75 (1.80–1.96 times longer than hand without pedicel)]. Leg I: trochanter 0.44/0.24 (1.83) [0.40–0.47/0.24–0.26 (1.62–1.88)], femur 1.48/0.18 (8.22) [1.44–1.66/0.19–0.22 (7.19–7.68)], patella 0.88/0.17 (5.18) [0.81–0.97/0.17–0.19 (4.50–5.11)], tibia 1.21/0.14 (8.64) [1.17–1.40/0.13–0.14 (8.36–10.00)], basitarsus 0.62/0.11 (5.64) [0.58–0.69/0.11–0.13 (4.77–5.91)], telotarsus 0.73/0.12 (6.08) [0.73–0.87/0.11–0.13 (6.00–7.25)]. Leg IV: trochanter 0.75/0.26 (2.88) [0.68–0.78/0.20–0.26 (2.62–3.45)], femur + patella 2.29/0.27 (8.48) [2.14– 2.48/0.25–0.32 (7.06–8.56)], tibia 2.18/0.19 (11.47) [2.03–2.39/0.17–0.20 (10.90–12.35)], basitarsus 0.80/0.14 (5.71) [0.72–0.92/0.13–0.15 (5.14–6.13)], telotarsus 0.99/0.14 (7.07) [0.92–1.13/0.13–0.15 (6.53–8.07)].

Females (paratypes). Body length 3.36–5.92. Carapace 1.23–1.31/0.98–1.10 (1.17–1.27). Pedipalpal trochanter 1.06–1.19/0.32–0.34 (3.18–3.50), femur 2.30–2.56/0.29–0.32 (7.44–8.28), patella 2.41–2.64/0.32–0.36 (6.81–7.59), chela (with pedicel) 3.88–4.23/0.48–0.54 (7.31–8.35), chela (without pedicel) 3.55–3.89/0.48–0.54 (6.72–7.69), hand length (without pedicel) 1.31–1.50, movable finger length 2.45–2.65 (1.77–1.95 times longer than hand without pedicel). Leg I: trochanter 0.37–0.45/0.23–0.26 (1.56–1.73), femur 1.43–1.53/0.20–0.21 (6.81–7.50), patella 0.79– 0.91/0.18–0.20 (3.95–4.79), tibia 1.13–1.29/0.13–0.14 (8.07–9.54), basitarsus 0.59–0.64/0.11–0.13 (4.62–5.45), telotarsus 0.76–0.84/0.12–0.14 (5.43–7.00). Leg IV: trochanter 0.74–0.80/0.25–0.28 (2.64–3.00), femur + patella 2.12–2.44/0.27–0.32 (6.63–8.71), tibia 2.08–2.31/0.17–0.19 (10.95–13.24), basitarsus 0.75–0.84/0.13–0.15 (5.00– 6.46), telotarsus 0.96–1.03/0.13–0.16 (6.13–7.85).

Remarks. Bisetocreagris tenuipalma sp. nov. is similar to B. baozinensis Mahnert et Li, 2016 , but can be distinguished by the presence of 4 eyespots on the slightly raised carapace surface (vs. B. baozinensis without eyes or eyespots); the pedipalpal femur 7.86–8.45 (♂), 7.44–8.28 (♀) vs. 7.0‒7.7 (♂ ♀) times longer than wide, the patella 7.44–8.13 (♂), 6.81–7.59 (♀) vs. 6.4‒7.0 (♂), 6.0‒6.1 (♀) times longer than wide in B. baozinensis ; and the presence of fine granules on pedipalp hand (vs. smooth in B. baozinensis ).

Bisetocreagris tenuipalma sp. nov. is similar to B. sanmen sp. nov. in having a similar pedipalpal, but differs by the presence of 4 eyespots on the slightly raised surface of carapace (vs. with 2 faint eyespots on a flat surface in B. sanmen sp. nov.), the pedipalpal patella 7.44–8.13 (♂), 6.81–7.59 (♀) vs. 6.35–6.53 (♂), 6.07–6.75 (♀) times longer than wide, and the chela (with pedicel) 8.37–8.82 (♂), 7.31–8.35 (♀) vs. 6.71–6.83 (♂), 5.90–6.48 (♀) times longer than wide in B. sanmen sp. nov.

This new species is similar, in pedipalpal proportions, to B. changbing sp. nov., but can be distinguished by the presence of 4 eyespots on the slightly raised surface of carapace (vs. with 2 faint eyespots in B. changbing sp. nov.), the pedicel about half the entire length of patella (vs. the pedicel obviously more than half the entire length of pedipalp patella in B. changbing sp. nov.), the movable finger 1.77–1.95 vs. 1.50–1.75 times longer than hand without pedicel in B. changbing sp. nov., and the presence of fine granulation on the chelal hand (vs. smooth in B. changbing sp. nov.).

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 52. Sanjie Cave, type locality of Bisetocreagris tenuipalma sp. nov. A. Surrounding surface environment with cave entrance; B. Entrance; C. The passageway where the B. tenuipalma sp. nov. was collected (on the wall); D. Collecting specimens on the wall.

FIGURE 53. Live individuals of Bisetocreagris tenuipalma sp. nov. (A: male; B: female) on the wall.

FIGURE 54. Bisetocreagris tenuipalma sp. nov., A. Holotype male, dorsal view; B. Paratype female, dorsal view.

FIGURE 55. Bisetocreagris tenuipalma 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 56. Bisetocreagris tenuipalma 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. Galea; F. Subterminal tarsal seta; 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–D, F), 0.25 mm (B, G–H), 0.5 mm (A), 1 mm (I–M).