Lagynochthonius hepingensis, Sun & Guo & Zhang, 2024

Sun, Jianzhou, Guo, Xiangbo & Zhang, Feng, 2024, Five new epigean Lagynochthonius species (Pseudoscorpiones, Chthoniidae) from southern China, ZooKeys 1198, pp. 101-134 : 101

Lagynochthonius hepingensis sp. nov.

Figs 10 , 11 , 12 , 13 Chinese name: 和平拉伪蝎

Type material.

Holotype ♂ (Ps.-MHBU-GZ2022080701): China, Guizhou Province, Qianxinan Prefecture, Wangmu County, Dayi Town, Heping Village, Near Provincial Highway 209, under topsoil and in the leaf litter layer [25°23′54.8″N, 106°7′37.08″E], 1553 m a.s.l., 7 August 2022, Yanmeng Hou, Lu Zhang, Jianzhou Sun & Wenlong Fan leg. Paratypes: 5 ♂ (Ps.-MHBU-GZ2022080702-06) and 2 ♀ (Ps.-MHBU-GZ2022080707-08), all with the same data as the holotype.

Etymology.

Named after the Heping Village, the type locality. A noun in apposition.

Diagnosis.

(♂♀). Moderately sized epigean species; carapace with four eyes, anterior margin smooth and epistome hump-shaped; tergites I-IV each with four setae. Rallum with seven blades. Pedipalps slender, chela 6.08-6.82 (♂), 5.33-5.44 (♀) × as long as broad; femur 6.25-7.00 (♂), 6.20-6.30 (♀) × as long as broad; both chelal fingers with intercalary teeth, fixed chelal finger with a modified accessory tooth (td) on prolateral-retrolateral face; chemosensory setae (sc) present on dorsum of chelal hand; sensilla present.

Description.

Males (holotype and paratypes) (Figs 10A , 11A-F , 12 , 13 ).

Color generally pale yellow, chelicerae, carapace, pedipalps and tergites slightly darker.

Cephalothorax (Figs 11D , 12A ): carapace nearly subquadrate, 0.97-1.03 × as long as broad, strongly constricted basally; posterior region with squamous sculpturing laterally, other area smooth, without furrows; anterior margin smooth, without serrate; epistome small and hump-shaped; four well-developed eyes; with 18 setae arranged s4s: 4: 4: 2: 2, most setae heavy, long and gently curved, anterolateral setae much shorter than others; with two pairs of lyrifissures, first pair situated middle to the setae of ocular row, second pair situated lateral to the sole pair of setae of posterior row. Manducatory process with two acuminate distal setae, anterior seta less than 1/2 length of medial seta; apex of coxa I with a rounded anteromedial process; coxae II with 8-10 terminally indented coxal spines on each side, set as an oblique and arc row, central spines slightly longer than the others (Fig. 12D ); intercoxal tubercle absent; Chaetotaxy of coxae: P 3, I 3, II 4, III 5, IV 5.

Chelicera (Figs 11C , 12B ): almost as long as carapace, 1.63-1.81 × as long as broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal setae shorter than others; movable finger with one medial seta. Cheliceral palm has moderate wrinkle on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 9-12 teeth, distal one largest; movable finger with 12-15 retrorse contiguous small teeth; galea completely vestigial (Fig. 12B ). Serrula exterior with 16-23 and serrula interior with 14-20 blades. Rallum with eight blades, the distal one longest and recumbent basally, with fine barbules and slightly set apart from the other blades, latter tightly grouped and with long pinnae, some of which are subdivided (Fig. 12C ).

Pedipalp (Figs 11A, B , 11E , 12E , 13A, B ): trochanter 1.50-1.78, femur 6.25-7.00, patella 2.11-2.88, chela 6.08-6.82, hand 2.83-3.10 × as long as broad; femur 2.43-2.84 × as long as patella; movable chelal finger 1.11-1.27 × as long as hand and 0.53-0.57 × as long as chela. Setae generally long and acuminate. Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized. Fixed chelal finger and hand with eight trichobothria, movable chelal finger with four trichobothria, ib and isb situated close together, submedially on dorsum of chelal hand; eb, esb and ist at base of fixed chelal finger; esb and eb at almost the same level and ist slightly distal to esb; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, close to chelal teeth; dx situated distal to et; sb slightly closer to st than to b; b and t situated subdistally, t situated at the same level as it and distal to b; est situated distal to b and close to it (Figs 11A , 13A ). Fixed chelal finger with sensilla af1-2 close together, near tip; movable chelal finger with four sensilla: am1-2 near tip, p2 slightly distad of sb, p1 proximad of sb and very close to chelal teeth (Fig. 13A ). Microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 11B , 13B ). Both chelal fingers with a row of teeth, spaced regularly along the margin, teeth smaller distally and proximally: fixed finger with 16-20 well-spaced, pointed teeth, plus 5-7 intercalary microdenticles, and a modified accessory tooth on prolateral-retrolateral face (td, slightly distal to dx); movable finger with seven or eight well-spaced, pointed teeth, plus 2-5 intercalary microdenticles and six or seven vestigial, rounded and contiguous basal teeth.

Opisthosoma: generally typical, pleural membrane finely granulated. All tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy I-XII: 4: 4: 4: 4: 4: 4-5: 5-6: 5-7: 5-6: 4: T2T: 0. Sternal chaetotaxy IV-XII: 8-12: 10-12: 10-13: 10-12: 11-12: 10-12: 9: -: 2. Genital region: sternite II with 10 setae scattered on median area, genital opening slit-like, sternite III with 16-18 setae (Fig. 11F ).

Legs (Fig. 13C, D ): fine granulation present on anterodorsal faces of trochanter IV, femur I; scale-like texture display on anterodorsal faces of femoropatella IV. Leg I: femur 1.69-2.00 × as long as patella; tarsus 1.93-2.36 × as long as tibia. Leg IV: femoropatella 2.40-2.67 × as long as deep; tibia 4.00-4.71 × as long as deep; with basal tactile setae on both tarsal segments: basitarsus 2.50-2.80 × as long as deep (TS = 0.33-0.43), telotarsus 8.75-11.67 × as long as deep and 2.33-2.64 × as long as basitarsus (TS = 0.24-0.30). Setae of leg I (trochanter to tibia) 3-4: 8-10: 6-7: 7-10, setae of leg IV (trochanter to basitarsus) 2-3: 3-4: 6-8: 7-9: 6-10. Arolium not divided, slightly shorter than the simple claws.

Adult females (paratypes) (Figs 10B , 11G ). Mostly same as males; tergal chaetotaxy I-XII: 4: 4: 4: 4-5: 5-6: 6: 6: 6-8: 6: 4: T2T: 0; sternal chaetotaxy IV-XII: 10-12: 12-13: 12-14: 11-12: 10-12: 8-11: 10: -: 2. Genital region: sternite II with 10 setae scattered on median area, sternite III with a row of 12 setae.

Dimensions (length/breadth or, in the case of the legs, length/depth in mm; ratios in parentheses). Males: body length 1.18-1.38. Pedipalps: trochanter 0.14-0.16/0.08-0.10 (1.50-1.78), femur 0.50-0.56/0.08-0.09 (6.25-7.00), patella 0.19-0.23/0.08-0.09 (2.11-2.88), chela 0.67-0.75/0.10-0.12 (6.08-6.82), hand 0.31-0.35/0.10-0.12 (2.83-3.10), movable chelal finger length 0.37-0.42. Chelicera 0.26-0.32/0.16-0.18 (1.63-1.81), movable finger length 0.15-0.18. Carapace 0.31-0.37/0.34-0.38 (0.89-1.09). Leg I: trochanter 0.10-0.12/0.07-0.10 (1.20-1.57), femur 0.26-0.30/0.05-0.06 (4.50-6.00), patella 0.15-0.16/0.05-0.06 (2.67-3.20), tibia 0.13-0.16/0.04 (3.25-4.00), tarsus 0.29-0.33/0.03-0.04 (7.25-11.00). Leg IV: trochanter 0.14-0.18/0.10-0.11 (1.36-1.63), femoropatella 0.44-0.50/0.17-0.20 (2.40-2.67), tibia 0.29-0.33/0.07-0.08 (4.00-4.71), basitarsus 0.13-0.15/0.05-0.06 (2.50-2.80), telotarsus 0.34-0.37/0.03-0.04 (8.75-11.67).

Females: body length 1.34-1.43. Pedipalps: trochanter 0.15-0.18/0.11-0.12 (1.25-1.64), femur 0.63-0.64/0.10 (6.20-6.30), patella 0.24-0.25/0.11-0.12 (2.08-2.18), chela 0.83-0.87/0.15-0.16 (5.33-5.44), hand 0.41-0.44/0.15-0.16 (2.73-7.75), movable chelal finger length 0.51-0.52. Chelicera 0.34-0.39/0.20 (1.70-1.95), movable finger length 0.21-0.23. Carapace 0.38-0.39/0.42 (0.90-0.93). Leg I: trochanter 0.11-0.13/0.09-0.10 (1.10-1.44), femur 0.32/0.06-0.07 (4.57-5.33), patella 0.16-0.17/0.06 (2.67-2.83), tibia 0.16-0.17/0.05 (3.2-3.4), tarsus 0.34-0.35/0.04-0.05 (6.80-8.75). Leg IV: trochanter 0.16-0.18/0.11-0.12 (1.45-1.50), femoropatella 0.54-0.55/0.18-0.21 (2.62-3.00), tibia 0.33-0.35/0.08-0.09 (3.89-4.12), basitarsus 0.16/0.06 (2.67), telotarsus 0.39/0.04 (9.75).

Remarks.

Lagynochthonius hepingensis sp. nov. most closely resembles L. tonkinensis in the presence of intercalary teeth on both chelal fingers and the presence of four setae on both tergal chaetotaxy I-II. However, it differs by the presence of a hump-shaped epistome and four well-developed eyes, whereas L. tonkinensis has a flat, rounded epistome and spot-like posterior pair of eyes ( Beier 1951).

Distribution.

China (Guizhou Province).

Figures

Figure 10. Lagynochthonius hepingensis sp. nov. A holotype male (dorsal view) B paratype female (dorsal view).

Figure 11. Lagynochthonius hepingensis sp. nov., holotype male (A-F) paratype female (G): A left chela (lateral view) B left chela (dorsal view) C left chelicera (dorsal view) D carapace (dorsal view) E left pedipalp (minus chela, dorsal view) F male genital area (ventral view) G female genital area (ventral view).

Figure 12. Lagynochthonius hepingensis sp. nov., holotype male A carapace (dorsal view) B right chelicera (dorsal view), with details of teeth C rallum D coxal spines on coxae II (ventral view) E left pedipalp (minus chela, dorsal view).

Figure 13. Lagynochthonius hepingensis sp. nov., holotype male A left chela (lateral view), with details of teeth and trichobothrial pattern B left chela (dorsal view) C leg I (lateral view) D leg IV (lateral view). Abbreviations: for the chelal trichobothria: b = basal; sb = sub-basal; st = subterminal; t = terminal; ib = interior basal; isb = interior sub-basal; ist = interior sub-terminal; it = interior terminal; eb = exterior basal; esb = exterior sub-basal; est = exterior sub-terminal; et = exterior terminal. For other abbreviations: af, apical sensilla of fixed chelal finger, am, apical sensilla of movable chelal finger; dx, duplex trichobothria; p 1 - 2, proximal sensilla of movable chelal finger; td, modified tooth.