Bisetocreagris baozinensis, Volker Mahnert & Yun-chun Li, 2016

Volker Mahnert & Yun-chun Li, 2016, Cave-inhabiting Neobisiidae (Arachnida: Pseudoscorpiones) from China, with description of four new species of Bisetocreagris Ćurčić, Revue suisse de Zoologie 123, pp. 259-268 : 264-265

Bisetocreagris baozinensis n.sp.

Figs 11-16

Holotype: MSWU; ♀; China, Sichuan Province, Gu Lin, Yu Hua Town , Bao Zi Cave , alt. 954 m, 28°01458’N 106°05209’E; 22 April 2014; coll. Yunchun Li and Yu-Cheng Lin.

Paratypes: 1♂ (in MSWU), 1♂, 1♀ (in MHNG); same data as for holotype.

Diagnosis: Troglobiomorphic habitus; carapace without eyes or eye-spots, with 6-8 setae on posterior margin; anterior tergites with 6-8 marginal setae; teeth on movable cheliceral finger on thickened lamella; galea present, divided into two main branches, each with forked apex; 6-7 setae on hand; rallum with 9-11 pinnate setae, distal one with an expanded base. Pedipalp: femur 7.0-7.7 times (length 2.17-2.33), patella 6.0-7.0 (length 2.05-2.29) longer than broad, club slightly longer (1.10-1.18 times) than pedicel, hand with pedicel 3.0-3.3 times (length 1.54-1.71), chela with pedicel 7.2-8.2 times (length 3.81-4.08) longer than broad, finger 1.34-1.47 times longer than hand with pedicel (length 2.22-2.42). Trichobothria: et-it at same level near fingertip, est slightly nearer to et than to ist, 5 trichobothria at finger base and on hand, sb on movable finger indistinctly nearer to b than to st.

Etymology: Latinized adjective derived from the name of the cave Bao Zi.

Description of females (males in parentheses, if different): Carapace, chelicerae and pedipalps yellowish brown, legs and abdominal segments yellowish. Carapace nearly as long as broad to 1.2 times longer than broad, smooth, anterior margin without epistome but with a small rounded knob; eyes or eye-spots absent; with 23-25 setae (6/7/3-5/7). Tergites with 7-9 (exceptionally 6 or 10) marginal setae, tergite XI 7 (with at least 2 tactile setae, most setae broken off). Manducatory process rounded, with 5 (1♀ with 4 on left side) marginal setae, pedipalpal coxa with 6-8 setae, coxa I with rounded medial corner, 6-8, II 5-8, III 4-5, IV 8-10. Genital operculum of ♀ with 18-19 medial setae (2 groups: 8-9/ 10 in marginal and discal position), sternite III with 18-21 marginal setae (a few medial ones in submarginal position)+ 2x 4-5; IV 12 + 2x 4 suprastigmal setae, followed by mainly 13-15 (♂ 15-16) uniseriate setae, XI 4-6 setae; genital operculum of ♂ with about 46-48 setae, genital opening with 6-7 short internal setae on each side; median genital sac short (reaching anterior half of sternite IV), wrinkled and widened distally, lateral sacs short, caudally bent; sternite III with anteromedian groove flanked on each side with 1 stout tiny seta; III with 26-29 setae (9-11 in discal position)+ 2x 5, IV 12-13 + 2x 3-4 suprastigmal setae. Anal cone with 2/2 setae. Pleural membrane granular.

Chelicera ( Fig. 11 ): With 6-7 long, slender setae on hand, fixed finger with 11-14 triangular uniform teeth, movable finger with 14-16 teeth, the medial ones on elevated lamella; galea ( Fig. 12 ) divided in 2 main branches, each one apically forked (only one of the 8 galeae examined undamaged), subgaleal seta not reaching fingertip; serrula exterior with 36-42, serrula interior with 28-32 blades. Rallum ( Fig. 13 ) with 9-11 pinnate setae, base of first seta slightly enlarged.

Pedipalp (♂♀) ( Figs 14-15 ): All segments smooth, setae long and smooth; trochanter 2.9-3.1 times longer than broad, with a tiny ventral hump distal of middle, femur distally slightly thickened, 7.0-7.7 times, patella 6.0-6.1 (♂: 6.4-7.0) times longer than broad, pedicel about half of patella length, club 1.1-1.2 times longer than pedicel, hand with pedicel 3.0-3.3 times, chela with pedicel 7.2- 8.2 times, without pedicel 6.5-7.6 times longer than broad, finger 1.3-1.5 times longer than hand with pedicel; fixed finger with 171-184 small cusped teeth (row about 10 teeth shorter than on movable finger), movable finger with 172-192 small teeth, cusped only in distal fourth of finger; very short venom duct in fixed finger. Five trichobothria grouped at base of fixed finger and on hand, est slightly distal of finger middle, et-it on same level near fingertip, on movable finger st nearer to t than to sb, the latter slightly nearer to b than to st ( Fig. 15 ).

Leg I: Femur 5.3-5.9 times, patella 4.0-4.7 times, tibia 7.4-9.0 times, basitarsus 3.8-4.3 times, telotarsus 4.9- 5.6 times longer than deep, femur 1.5 times longer than patella, telotarsus 1.3-1.4 times longer than basitarsus. Leg IV ( Fig. 16 ): Femur+patella 6.3-7.4 times longer than deep, femur shorter than patella, tibia 10.1-10.6 times, basitarsus 3.8-4.6 times, telotarsus 5.3-5.8 times longer than deep, telotarsus 1.2-1.3 times longer than basitarsus; subterminal seta ( Fig. 16 a) forked in distal half; both branches dentate, claws slender and smooth; arolia shorter than claws; tactile setae probably present on tibia (TS=0.43-0.46), on basitarsus (TS=0.13), and on telotarsus (TS= about 0.50), but all setae fallen off.

Measurements of ♀ (♂ in parentheses): Body length 4.48-4.59 (3.97-4.48); carapace 1.14-1.29/1.00-1.16 (1.17-1.24/1.00-1.10). Pedipalp: trochanter 1.07- 1.08/0.34-0.37 (0.98-1.07/0.32-0.34), femur 2.25- 2.27/0.32-0.33 (2.17-2.33/0.30), patella 2.12-2.13/0.35 (2.05-2.29/0.32-0.33), length of pedicel 0.97-0.99 (0.97- 1.08), hand with pedicel 1.66-1.71/0.53-0.55 (1.54- 1.65/0.47-0.53), length of pedicel 0.31-0.32 (0.27-0.34), length of finger 2.40-2.42 (2.22-2.27), length of chela with pedicel 4.04-4.08 (3.81-3.84), without pedicel 3.72-3.77 (3.49-3.55). Leg I: femur 1.22-1.23/0.22- 0.23 (1.21-1.31/0.21-0.22), patella 0.81-0.82/0.20- 0.21 (0.80-0.86/0.18-0.19), tibia 1.17-1.31/0.15-0.16 1.15-1.21/0.13-0.14), basitarsus 0.54-0.55/0.14 (0.54- 0.56/0.13-0.14), telotarsus 0.76-0.77/0.14-0.15 (0.72- 0.76/0.15-0.16). Leg IV: femur+patella 2.07-2.08/0.28- 0.32 (1.96-2.14/0.29-0.31), length of femur 0.93-0.95 (0.90-0.93), tibia 1.97-2.02/0.19-0.20 (1.95-2.14/0.19- 0.20), basitarsus 0.70/0.16-0.18 (0.64-0.73/0.15), telotarsus 0.87-0.88/0.16-0.17 (0.84-0.85/0.14-0.15).

Remarks: Bisetocreagris baozinensis n. sp. belongs to a group of species ( B. chinacavernicola n. comb., B. cavernarum n. sp., B. martii n. comb., B. chuanensis n. sp.) possessing a long patellar pedicel which is about half of the total patella length. The new species clearly differs from B. martii n. comb. by the absence of eyes and by much more slender and longer pedipalps (e.g. femur 7.0-7.7 times, length 2.17-2.33 vs 4.25 times, length 1.58). Bisetocregaris cavernarum n. sp. and B. chuanensis n. sp. possess two or four indistinct eyes (vs absence of eye-spots in B. baozinensis n. sp.) and have stouter and shorter pedipalps (e.g. femur max. 5.8 times longer than broad, length max. 2.10 vs min. 7.0 times, length min. 2.17 in B. baozinensis ).

Figures

Figs 11 - 23. (11 - 16) Bisetocreagris baozinensis n. sp., holotype ♀. (11) Left chelicera. (12) Galea. (13) Rallum. (14 - 15) Pedipalp (vestitural setae on chela omitted), trochanter to patella (14) and hand (15). (16) Leg IV (vestitural setae omitted, most fallen off), with detail of subterminal seta (16 a). (17 - 23) Bisetocreagris juanxuae n. sp., holotype ♀. (17) Left chelicera. (18) Galea of left and right cheliceral finger. (19) Rallum. (20 - 21) Pedipalp (vestitural setae of chela omitted), trochanter to patella (20) and hand (21). (22) Leg IV, femur + patella. (23) Tip of tarsus IV. Scales: 0.1 mm (12 - 13, 16 a); 0.3 mm (11,17, 23); 1.0 mm (14 - 15; 16; 20 - 21; 22).