Bisetocreagris xishui, 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 : 68-73

Bisetocreagris xishui sp. nov. (习ḳ双ŁÞ伪AE)

http://zoobank.org:act: 9D359E72-48FA-4FE8-8814-454B6388B1AA

Figs 57–59

Type material. Holotype male (Ps.- MHBU-GZ13100301 ): China, Guizhou Province, Zunyi City, Xishui County, Sangmu Town , Dongkoushang Cave (âṅåǎ义Ṅ习AE县NJÌDzñ口上ñ), 3 October 2013, Xuankong Jiang leg.

Paratypes: 2 males (Ps.- MHBU-GZ13100302‒03 ) , 1 female (Ps.- MHBU-GZ13100304 ), same data as the holotype .

Etymology. Named after the County of Xishui (习AE县), near the type locality; noun in apposition.

Distribution. This new species is known only from the type locality Dongkoushang Cave ( Fig. 1L ).

Diagnosis. (♂ ♀). Troglomorphic habitus; carapace with 2 eyespots on the slightly raised surface; epistome triangular; carapace with 8–10 setae on posterior margin; pedipalp slender and smooth except for medial of hand and base of femur, which is finely granular, both chelal fingers with 128–145 teeth; femur 5.58–5.82 times (length 2.06–2.21 (♂), 2.32 (♀ )), patella 4.53–4.60 times (length 1.84–1.95 (♂), 2.07 (♀ )) longer than wide, pedicel about half the entire length of patella. Hand with pedicel 2.39–2.47 (♂), 2.51 (♀) times (length 1.51–1.63 (♂), 1.76 (♀ )), chela with pedicel 5.34–5.48 (♂), 5.29 (♀) times (length 3.34–3.62 (♂), 3.70 (♀ )) longer than wide, finger 1.39–1.42 (♂), 1.32 (♀) times longer than hand with pedicel. Chelicera: rallum with 9–10 pinnate setae, distal one with a slightly expanded base.

Description. Male (holotyape; paratypes males in parentheses; Fig. 57A ). Carapace, chelicerae, and pedipalps yellowish brown; abdomen and legs yellowish.

Carapace ( Figs 58A , 59A–B ): smooth, 1.15 (1.26–1.29) times longer than wide, with a total of 29 (31–35) setae, including 4 (4–5) on anterior margin, 9 (8–10) on posterior margin, and 2 (2–3) on each side of antero-lateral margin; with 2 eyespots on the slightly raised surface ( Fig. 58B ); epistome triangular.

Chelicera ( Figs 58C , 59B–D, F ): hand with 6–7 (7) setae, movable finger with 1 submedial seta; fixed finger with 16–17 (15–18) teeth; movable finger with 16–18 (16–18) teeth; serrula exterior with 34–36 lamellae; serrula interior with 24–27 lamellae. Galea ( Figs 59D, F ) with only one main branch and apically forked. Rallum ( Fig. 59C ) with 9 pinnate blades, distal-most blade with slightly expanded base, proximal blade short.

Pedipalps ( Figs 58D–E , 59I–K ): apex of coxae rounded, with 4–5 setae on each side, pedipalpal coxae with 7–8 (6–9) setae. Pedipalp slender and smooth except for medial of hand and base of femur, which is finely granular. Trochanter 2.36 (2.41–2.48) times longer than wide, femur 5.72 (5.58–5.82), patella 4.60 (4.53–4.59) times longer than wide, pedicel about half the entire length of patella, chela (with pedicel) 5.39 (5.34–5.48), chela (without pedicel) 4.97 (4.86–5.03) times longer than wide, movable finger 1.63 (1.66–1.68) 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 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, the distance between sb and st longer than that of sb between b ( Figs 58D , 59I–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 132 (128) teeth of unequal length, which are blunt and retrorse in distal and middle part, flat and the length is unequal in basal part; movable finger with 139 (137) teeth, which are blunt and retrorse in the distal and middle part but flat and round more basally; all teeth contiguous.

Abdomen: pleural membrane granulated. Tergal chaetotaxy (I–XI): 10:10:8:10:11:12:11:13:13:12:11 (11:9– 10:9–10:11:12:13:12–14:11–13:13–14:11–13:10–11); sternal chaetotaxy (V–XI):10:17:18:16:20:19:16:5 (11:18– 19:18–19:19–20:20:17–19:14–15:5–6); stigmata with 5–6 (4–7) setae; anal cone with 2 dorsal and 2 ventral setae. Male genital area ( Figs 58F , 59G ): sternite II with 42 (43–44) scattered setae; sternite III with anteromedian groove flanked by one small seta on each side, with 21 (24–26) posterior setae.

Legs: coxa chaetotaxy (I–IV): 9:8–9:5:9 (9–11:8–10:5–6:11–13). Leg I ( Figs 58H , 59L ): femur 4.50 (4.58– 4.75), patella 3.50 (3.52–3.75), tibia 5.94 (6.53–6.87), basitarsus 3.00 (3.14–3.46), telotarsus 4.71 (4.93–5.14) times longer than wide, femur 1.54 (1.47–1.54) times longer than patella, telotarsus 1.57 (1.57–1.60) times longer than basitarsus.

Leg IV ( Figs 58I , 59E, M ): femur + patella 4.97 (5.61–6.03) times longer than wide, femur shorter than patella, tibia 8.65 (8.75–8.95), basitarsus 3.63 (3.81–4.00), telotarsus 5.00 (5.53–5.60) times longer than wide, telotarsus 1.38 (1.36–1.40) times longer than basitarsus; basitarsus with one tactile seta (TS=0.13–0.16), telotarsus with one tactile seta (TS=0.46–0.51); subterminal tarsal seta ( Fig. 59E ) bifurcate, both branches dentated; arolium not divided, shorter than the slender and simple claws.

Female (paratype; Fig. 57A ): mostly same as holotype and paratypes males.

Chelicera. Hand with 6–7 setae, movable finger with 1 submedial seta; fixed finger with 15–16 teeth; movable finger with 18–19 teeth; serrula exterior with 37 lamellae; serrula interior with 26 lamellae. Galea with only one main branch and apically forked; rallum of 10 blades, and similar to holotype.

Pedipalps. Apex of coxae rounded, with 5 setae on each side. Pedipalpal coxae with 8 setae. Trochanter 2.36, femur 5.66, patella 4.60, chela (with pedicel) 5.29, chela (without pedicel) 4.86 times longer than wide, movable finger 1.56 times longer than hand (without pedicel). Fixed chelal finger with about 135 teeth, movable finger with about 145 teeth.

Abdomen. Tergal chaetotaxy (I–XI): 11:9:11:11:12:12:12:13:12:12:2; sternal chaetotaxy (IV–XI): 9:18:19:19:18:18:15:5. Female genital area ( Figs 58G , 59H ): sternite II with 4–6 setae on each side; sternite III with a row of 15 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 4.80 [4.17–4.60]. Carapace 1.20/1.04 (1.15) [1.33–1.35/1.03– 1.07 (1.26–1.29)]. Pedipalpal trochanter 0.92/0.39 (2.36) [0.94–0.99/0.39–0.40 (2.41–2.48)], femur 2.06/0.36 (5.72) [2.12–2.21/0.38 (5.58–5.82)], patella 1.84/0.40 (4.60) [1.88–1.95/0.41–0.43 (4.53–4.59)], chela (with pedicel) 3.34/0.62 (5.39) [3.42–3.62/0.64–0.66 (5.34–5.48)], chela (without pedicel) 3.08/0.62 (4.97) [3.11–3.32/0.64–0.66 (4.86–5.03)], hand length (without pedicel) 1.30 [1.30–1.37], movable finger length 2.12 (1.63 times longer than hand without pedicel) [2.18–2.27 (1.66–1.68 times longer than hand without pedicel)]. Leg I: trochanter 0.32/0.27 (1.19) [0.38/0.27 (1.41)], femur 1.08/0.24 (4.50) [1.10–1.14/0.24 (4.58–4.75)], patella 0.70/0.20 (3.50) [0.74– 0.75/0.20–0.21 (3.52–3.75)], tibia 0.95/0.16 (5.94) [0.98–1.03/0.15 (6.53–6.87)], basitarsus 0.42/0.14 (3.00) [0.44– 0.45/0.13–0.14 (3.14–3.46)], telotarsus 0.66/0.14 (4.71) [0.69–0.72/0.14 (4.93–5.14)]. Leg IV: trochanter 0.65/0.27 (2.41) [0.63–0.67/0.28 (2.25–2.39)], femur + patella 1.79/0.36 (4.97) [1.85–1.87/0.31–0.33 (5.61–6.03)], tibia 1.73/0.20 (8.65) [1.75–1.88/0.20–0.21 (8.75–8.95)], basitarsus 0.58/0.16 (3.63) [0.60–0.61/0.15–0.16 (3.81–4.00)], telotarsus 0.80/0.16 (5.00) [0.83–0.84/0.15 (5.53–5.60)].

Female (paratype). Body length 4.33. Carapace 1.40/1.14 (1.23). Pedipalpal trochanter 0.99/0.42 (2.36), femur 2.32/0.41 (5.66), patella 2.07/0.45 (4.60), chela (with pedicel) 3.70/0.70 (5.29), chela (without pedicel) 3.40/0.70 (4.86), hand length (without pedicel) 1.49, movable finger length 2.33 (1.56 times longer than hand without pedicel). Leg I: trochanter 0.37/0.28 (1.32), femur 1.21/0.24 (5.04), patella 0.80/0.20 (4.00), tibia 1.09/0.15 (7.27), basitarsus 0.46/0.14 (3.29), telotarsus 0.75/0.14 (5.36). Leg IV: trochanter 0.69/0.30 (2.30), femur + patella 1.96/0.33 (5.94), tibia 1.95/0.20 (9.75), basitarsus 0.63/0.16 (3.94), telotarsus 0.87/0.16 (5.44).

Remarks. The new species resembles B. cavernarum Mahnert et Li, 2016 , B. chinacavernicola ( Schawaller, 1995) , B. guangshanensis Gao et Zhang, 2017 and B. maomaotou Gao, Wynne et Zhang, 2018 in having a similar slender pedipalp and the pedipalpal pedicel about half the entire length of pedipalpal patella, but can be distinguished by the presence of 2 eyespots (vs. B. cavernarum with 4 small eyes; B. maomaotou without eyes or eyespots), the pedipalpal femur 5.66 (♀) times longer than wide (vs. 5.20 (♀) times in B. maomaotou ), the chela (without pedicel) 4.86 times longer than wide (vs. 4.24 times in B. maomaotou ), and the presence of fine granulation on the medial face of pedipalp chela hand and base of femur (vs. distal part of hand dorsally and medially finely granular in B. cavernarum ; smooth in B. chinacavernicola ; all segments scale-like sculptured, except chela in B. guangshanensis ).

Bisetocreagris xishui sp. nov. also resembles B. jiangi sp. nov. by having a similar pedipalpal. The new species differs by the pedipalpal femur 5.58–5.82 (♂), 5.66 (♀) times longer than wide (vs. 6.32–6.77 (♂), 6.12–6.79 (♀) times in B. jiangi sp. nov.), the patella 4.53–4.60 (♂), 4.60 (♀) times longer than wide (vs. 5.40–5.48 (♂), 5.03–5.47 (♀) times in B. jiangi sp. nov.), the chela (without pedicel) 4.86–5.03 (♂), 4.86 (♀) times longer than wide (vs. 5.60–5.82 (♂), 4.92–5.58 (♀) times in B. jiangi sp. nov.), and the presence of finely granular on medial face of pedipalp chela hand and base of femur (vs. smooth in B. jiangi sp. nov.).

Bisetocreagris xishui sp. nov. also resembles B. chumi sp. nov. in having a similar pedipalpal. The new species differs by the pedipalpal femur 5.58–5.82 (♂), 5.66 (♀) vs. 6.52–6.78 (♂), 6.37–6.77 (♀) times longer than wide, the patella 4.53–4.60 (♂), 4.60 (♀) vs. 4.80–5.41 (♂), 4.88–5.54 (♀) times longer than wide in B. chumi sp. nov., the chela (with pedicel) 5.34–5.48 (♂), 5.29 (♀) vs. 5.92–6.29 (♂), 5.51–5.95 (♀) times longer than wide in B. chumi sp. nov., and the presence of finely granular medially on pedipalp hand and base of femur (vs. hand with fine granulations in B. chumi 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 57. Bisetocreagris xishui sp. nov., A. Holotype male, dorsal view; B. Paratype female, dorsal view.

FIGURE 58. Bisetocreagris xishui 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 59. Bisetocreagris xishui 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).