Bisetocreagris longidigitata, 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 : 46-51

Bisetocreagris longidigitata sp. nov. (RDz双ŁÞ伪AE)

http://zoobank.org:act: 7A16E462-3CCA-41DD-BC97-7275F79B03D4

Figs 37–41

Type material. Holotype male (Ps.- MHBU-GZ19080201 ): China, Guizhou Province, Guiding County, Yanshan Town, Mao’er Cave (âṅåâî县ẠƜDzĕ儿ñ), [26°24′22.49″N, 107°7′36.75″E], 1088 m a.s.l., 8 August 2019, Zegang Feng & Chen Zhang leg.

Paratypes: 3 females (Ps.- MHBU-GZ19080202‒04 ), same data as the holotype .

Etymology. The specific name is derived from a combination of the Latin word “ longus ” and “ digitus ”, meaning long and finger, respectively, and referring to the elongated chelal finger.

Distribution and habitat. This new species is known only from the type locality Mao’er Cave ( Figs 1C , 37 ), located ~ 5.5 km south of Yanshan Town, Guiding County. The limestone cave is located about 5 m next to a countryside road, but it is hidden by bamboo. The entrance is irregularly round (diameter ~ 1.5 m). The cave is divided into two main passageways, one may be used for drainage in flood season. All specimens were collected on the wall ( Fig. 37D ) of the dark zone.

Diagnosis. (♂ ♀). Troglomorphic habitus; carapace without eyes or eyespots; epistome small and triangular; carapace with 8–11 setae on posterior margin; pedipalp smooth and slender except for hand, which is finely granular, both chelal fingers with 116–129 teeth; femur 7.65–7.96 (♂ ♀) times (length 3.54–3.90), patella 6.67 (♂), 6.43–6.47 (♀) times (length 3.40 (♂), 3.60–3.82 (♀ )) longer than wide, pedicel about one-third of the entire length of patella. Hand with pedicel 2.54 (♂), 2.59–2.61 (♀) times (length 2.01 (♂), 2.16–2.27 (♀ )), chela with pedicel 6.55–6.76 (♂ ♀) times (length 5.20–5.81) longer than wide, finger 1.63–1.71 (♂ ♀) times longer than hand with pedicel. Chelicera: rallum with 11–13 pinnate setae, distal seta with an expanded base.

Description. Male (holotype; Fig. 39A ). Carapace, chelicerae, and pedipalps reddish brown; abdomen and legs yellowish.

Carapace ( Figs 40A , 41A–B ): smooth, 1.27 times longer than wide, with a total of 31 setae, including 4 on anterior margin, 9 on posterior margin, and 2 on each side of antero-lateral margin; without eyes or eyespots ( Fig. 40B ); epistome small and triangular.

Chelicera ( Figs 40C , 41B–C, E ): hand with 7 setae, movable finger with 1 submedial seta; fixed finger with 16–17 teeth; movable finger with 15–20 teeth; serrula exterior with 47 lamellae; serrula interior with 33 lamellae. Galea ( Fig. 41E ) divided into 2 main branches and apically forked. Rallum ( Fig. 41C ) with 11 pinnate blades, distal-most blade with slightly expanded base, distal-most 3 blades separated from others, proximal one short.

Pedipalps ( Figs 40D–E , 41I–K ): apex of coxae rounded, with 5 setae on each side, pedipalpal coxae with 10 setae. Pedipalp smooth and slender except for hand, which is finely granular. Trochanter 2.47 times longer than wide, femur 7.87, patella 6.67 times longer than wide, pedicel about one-thirds of the entire length of patella, chela (with pedicel) 6.58, chela (without pedicel) 6.03 times longer than wide, movable finger 2.08 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 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 st and t longer than that of sb between b ( Figs 40D , 41J–K ). Venom apparatus present only in fixed chelal finger, venom duct short, not extending past half of the distance to et. Fixed chelal finger with 116 pointed and retrorse teeth; movable finger with 122 teeth, which are pointed and retrorse in distal and middle part, blunt and round in basal part; all teeth contiguous.

Abdomen:pleural membrane granulated.Tergal chaetotaxy (I–XI): 10:9:8:8:9:8:10:9:11:12:8; sternal chaetotaxy (IV–XI): 8:15:17:17:18:17:15:6; stigmata with 6–9 setae; anal cone with 2 dorsal and 2 ventral setae. Male genital area ( Figs 40F , 41F ): sternite II with 25 scattered setae; sternite III with anteromedian groove flanked by one small seta on each side, with 46 posterior setae.

Legs: coxae chaetotaxy (I–IV): 11–14:10–14:5:13–15. Leg I ( Figs 40H , 41L ): femur 6.45, patella 4.78, tibia 10.06, basitarsus 5.47, telotarsus 8.13 times longer than wide, femur 1.45 times longer than patella, telotarsus 1.49 times longer than basitarsus.

Leg IV ( Figs 40I , 41D, M ): femur + patella 8.61 times longer than wide, femur shorter than patella, tibia 13.04, basitarsus 5.58, telotarsus 9.50 times longer than wide, telotarsus 1.43 times longer than basitarsus; basitarsus with one tactile seta (TS=0.13), telotarsus with one tactile setae (TS=0.67); subterminal tarsal seta ( Figs 41D ) bifurcated, both branches dentated; arolium not divided, shorter than the slender and simple claws.

Females (paratypes; Figs 38 , 39B ): mostly same as holotype male.

Chelicera. Hand with 6–7 setae, movable finger with 1 submedial seta; fixed finger with 14–22 teeth; movable finger with 15–21 teeth; serrula exterior with 43–48 lamellae; serrula interior with 33–34 lamellae. Galea divided into 2 main branches and apically forked; rallum with 12–13 blades and similar to holotype.

Pedipalps. Apex of coxae rounded, with 5 setae on each side. Pedipalpal coxae with 10–13 setae. Trochanter 2.41–2.55, femur 7.65–7.96, patella 6.43–6.47, chela (with pedicel) 6.55–6.76, chela (without pedicel) 6.03–6.21 times longer than wide, movable finger 2.02–2.12 times longer than hand (without pedicel). Fixed chelal finger with about 120–129 teeth, movable finger with about 122–128 teeth.

Abdomen. Tergal chaetotaxy (I–XI): 11–12:9–11:8–11:8:8–9:9–11:9–11:11–12:11–14:11–12:8–10; sternal chaetotaxy (IV–XI): 7–8:15–17:18–19:17–19:18–20:16–17:14–16:6. Female genital area ( Figs 40G , 41G ): sternite II with 4–9 setae on each side; sternite III with a row of 11–12 setae on the posterior margin.

Measurements: (length/breadth or depth in mm; ratios for most characters in parentheses). Male (holotype). Body length 6.39. Carapace 1.65/1.30 (1.27). Pedipalpal trochanter 1.21/0.49 (2.47), femur 3.54/0.45 (7.87), patella 3.40/0.51 (6.67), chela (with pedicel) 5.20/0.79 (6.58), chela (without pedicel) 4.76/0.79 (6.03), hand length (without pedicel) 1.63, movable finger length 3.39 (2.08 times longer than hand without pedicel). Leg I: trochanter 0.48/0.35 (1.37), femur 1.87/0.29 (6.45), patella 1.29/0.27 (4.78), tibia 1.81/0.18 (10.06), basitarsus 0.82/0.15 (5.47), telotarsus 1.22/0.15 (8.13). Leg IV: trochanter 1.02/0.39 (2.62), femur + patella 3.27/0.38 (8.61), tibia 3.26/0.25 (13.04), basitarsus 1.06/0.19 (5.58), telotarsus 1.52/0.16 (9.50).

Females (paratypes). Body length 6.60–7.48. Carapace 1.73–1.89/1.40–1.44 (1.22–1.35). Pedipalpal trochanter 1.25–1.35/0.50–0.54 (2.41–2.55), femur 3.70–3.90/0.47–0.49 (7.65–7.96), patella 3.60–3.82/0.56–0.59 (6.43– 6.47), chela (with pedicel) 5.49–5.81/0.83–0.87 (6.55–6.76), chela (without pedicel) 5.05–5.34/0.83–0.87 (6.03– 6.21), hand length (without pedicel) 1.74–1.85, movable finger length 3.51–3.82 (2.02–2.12 times longer than hand without pedicel). Leg I: trochanter 0.52–0.62/0.38 (1.37–1.63), femur 1.95–2.06/0.31–0.34 (5.94–6.29), patella 1.36–1.43/0.28–0.30 (4.72–4.86), tibia 1.79–1.86/0.19–0.20 (9.30–9.68), basitarsus 0.80–0.84/0.16–0.18 (4.67– 5.13), telotarsus 1.28–1.39/0.15–0.17 (8.00–8.73). Leg IV: trochanter 1.02–1.08/0.39–0.43 (2.49–2.72), femur + patella 3.39–3.44/0.38–0.41 (8.39–8.95), tibia 3.21–3.32/0.28–0.29 (11.07–11.86), basitarsus 1.09–1.13/0.21–0.22 (5.14–5.33), telotarsus 1.56–1.66/0.18–0.20 (8.30–9.00).

Remarks. Bisetocreagris longidigitata sp. nov. resembles B. gracilenta Gao et Zhang, 2017 and B. titania ( Mahnert, 2003) in having a similar pedipalpal, but differs by the pedipalpal femur 7.87 (♂), 7.65–7.96 (♀) times longer than wide (vs. 8.50 (♀) times in B. gracilenta ; 8.9 (♂) times in B. titania ), the patella 6.67 (♂), 6.43–6.47 (♀) times longer than wide (vs. 7.61 (♀) times in B. gracilenta ; 8.0 (♂) times in B. titania ), and the chela (with pedicel) 6.58 (♂), 6.55–6.76 (♀) times longer than wide (vs. 6.54 (♀) times in B. gracilenta ; 7.8 (♂) times 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 37. Mao’er Cave, type locality of Bisetocreagris longidigitata sp. nov., A. Surrounding surface environment with cave entrance; B. Entrance; C. The passageway where the B. longidigitata sp. nov. was collected; D. The habitat of B. longidigitata sp. nov. (on the wall).

FIGURE 38. Live individual of Bisetocreagris longidigitata sp. nov. (female) on the wall.

FIGURE 39. Bisetocreagris longidigitata sp. nov., A. Holotype male, dorsal view; B. Paratype female, dorsal view.

FIGURE 40. Bisetocreagris longidigitata 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 41. Bisetocreagris longidigitata sp. nov., holotype male (A–F, H–M), female (G). A. Carapace, dorsal view; B. Right chelicera, dorsal view; C. Rallum; D. Subterminal tarsal seta; E. Galea; F. Male genitalia, ventral view; G. Female genitalia, ventral view; H. Movable finger of chelicera, showing galea; I. Right pedipalp, minus chela, dorsal view; J. Right chela, dorsal view; K. Right chelal fingers, retrolateral view; L. Right leg I, lateral view; M. Right leg IV, lateral view. Scale bars: 0.1 mm (C–D, H), 0.25 mm (F–G), 0.5 mm (A–B), 1 mm (I–M).