taxonID	type	description	language	source
03DA1A1EFF9FFFA1FF053ECCE2B63DC9.taxon	type_taxon	Type species: Chthonius johni Redikorzev, 1922, by original designation.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF9FFFAEFF053F79E3C23D46.taxon	description	Figs 2 – 5	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF9FFFAEFF053F79E3C23D46.taxon	materials_examined	Type material. Holotype ♂ (Ps. - MHBU-GZC 190805 - 01): China, Guizhou Province, Panzhou City, Chengguan Town, Nanmen Village, Biyun Park, Biyun Cave, under the detritus and on the walls in the deep zone [25 ° 46 ′ 18.91 ″ N, 104 ° 38 ′ 24.0 ″ E], 1496 m a. s. l., 5 August 2019, Zegang Feng, Zhaoyi Li & Chen Zhang leg. Paratypes: 4 ♂ (Ps. - MHBU-HBUARA # 2022 - 498 - 01 – HBUARA # 2022 - 498 - 04), 2 ♀ (Ps. - MSWU-HBUARA # 2022 - 498 - 05 & HBUARA # 2022 - 498 - 06), with the same location as the holotype, 2 August 2022, Yanmeng Hou, Lu Zhang, Jianzhou Sun & Wenlong Fan leg.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF9FFFAEFF053F79E3C23D46.taxon	etymology	Etymology. Named after the type locality, Biyun Cave.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF9FFFAEFF053F79E3C23D46.taxon	diagnosis	Diagnosis (♂ ♀). Moderately sized troglomorphic species with elongated appendages; carapace without eyes or eyespots; anterior margin of carapace thin, finely denticulated, epistome small, pointed, triangular; posterior margin of carapace with two setae; tergites Ⅰ – Ⅴ each with four setae. Pedipalps slender, femur 8.06 (♂), 7.82 – 7.89 (♀) times longer than broad; chela 6.85 – 7.08 (♂), 7.27 – 7.43 (♀) times longer than broad; chelal fingers without intercalary teeth; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF9FFFAEFF053F79E3C23D46.taxon	description	Description. Males (holotype and paratypes) (Figs 2 F, 3 A, 4 A – F, 5). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 4 C, 5 A): carapace 1.00 times longer than broad, gently narrowed posteriorly; surface smooth, without furrows; no traces of eyes; anterior margin slightly serrate; epistome pointed and small, triangular; with 18 setae arranged s 4 s: 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 setae of ocular row, second pair situated lateral to the sole pair of setae of posterior row. Chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 5; manducatory process with two acuminate distal setae, anterior seta less than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with ten terminally indented coxal spines on each side, set as an oblique row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 5 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 4 D, 5 B): large, about as long as carapace, 2.40 – 2.47 times longer than broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 15 – 17 teeth, distal one largest; movable finger with 21 – 22 retrorse contiguous small teeth; galea absent (Fig. 5 B). Serrula exterior with 22 – 23 blades and serrula interior with 14 – 15 blades. Rallum with nine 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. 5 D). Pedipalp (Figs 4 A – B, E, 5 E – G): long and slender, trochanter 1.20 – 1.26, femur 8.06, patella 2.35, chela 6.85 – 7.08, hand 2.70 – 2.81 times longer than broad; femur 2.74 times longer than patella; movable chelal finger 1.49 – 1.52 times longer than hand and 0.59 – 0.60 times longer than chela. Setae generally long and acuminate; one distal lyrifissure present on patella (Figs 4 E, 5 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized, with weak granulation dorsally at base of fixed chelal finger and hand. 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 forming a straight oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb situated midway between b and st; b and t situated subdistally, t situated distal to it; est situated distal to b (Fig. 5 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, homodentate, spaced regularly along the margin, larger and well-spaced teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 29 – 30 macrodenticles, slightly retrorse and pointed; movable chelal finger with 27 – 29 macrodenticles (slightly smaller than teeth on fixed chelal finger), slightly retrorse and pointed (Fig. 5 F). Chelal fingers slightly curved in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 4 B, 5 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 4: 4: 4: 4: 4: 4 – 5: 4: 4 – 5: 4 – 5: 4: T 2 T: 0, tergites VIII – IX each with an unpaired median seta. Sternal chaetotaxy III – XII: 13 – 14: 12 – 14: 9: 9: 8 – 9: 9: 9: 9: 0: 2. Anterior genital operculum with ten setae, genital opening slit-like, with 11 – 13 marginal setae on each side, 34 in total (Fig. 4 F). Legs (Fig. 5 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of trochanter IV, femur Ⅰ, IV and patella IV. Femur of leg Ⅰ 1.79 – 1.86 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.38 – 2.47 times longer than tibia. Femoropatella of leg IV 4.33 – 4.38 times longer than deep; tibia 6.55 – 6.64 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 3.78 – 4.00 times longer than deep (TS = 0.32 – 0.34), tarsus 14.50 – 14.83 times longer than deep and 2.62 – 2.72 times longer than metatarsus (TS = 0.27 – 0.33). Arolium slightly shorter than the claws, not divided; claws simple. Adult females (paratypes) (Figs 3 B, 4 G). Mostly same as males, but a little larger; chaetotaxy of coxae: P 3, Ⅰ 3, II 3 – 4, III 5, IV 5; tergal chaetotaxy Ⅰ – XII: 4: 4: 4: 4: 4: 4: 4: 4: 4: 4: T 2 T: 0; sternal chaetotaxy IV – XII: 12 – 13: 10: 9: 9: 9: 9: 9: 0: 2; anterior genital operculum with ten setae, posterior margin with 12 – 14 marginal setae, 22 – 24 in total; leg IV with a long tactile seta on both tarsal segments: metatarsus 4.00 – 4.63 times longer than deep (TS = 0.32 – 0.34), tarsus 14.17 – 16.17 times longer than deep and 2.62 – 2.66 times longer than metatarsus (TS = 0.22 – 0.28). Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Males: body length 2.02 – 2.10. Pedipalps: trochanter 0.24 / 0.19 – 0.20 (1.20 – 1.26), femur 1.29 / 0.16 (8.06), patella 0.47 / 0.20 (2.35), chela 1.84 – 1.85 / 0.26 – 0.27 (6.85 – 7.08), hand 0.73 / 0.26 – 0.27 (2.70 – 2.81), movable chelal finger length 1.09 – 1.11. Chelicera 0.72 – 0.74 / 0.30 (2.40 – 2.47), movable finger length 0.39 – 0.40. Carapace 0.60 / 0.60 (1.00). Leg Ⅰ: trochanter 0.19 / 0.16 (1.19), femur 0.69 – 0.70 / 0.09 (7.67 – 7.78), patella 0.37 – 0.39 / 0.08 (4.63 – 4.88), tibia 0.32 / 0.06 (5.33), tarsus 0.76 – 0.79 / 0.05 – 0.06 (13.17 – 15.20). Leg IV: trochanter 0.27 – 0.29 / 0.16 (1.69 – 1.81), femoropatella 1.04 – 1.05 / 0.24 (4.33 – 4.38), tibia 0.72 – 0.73 / 0.11 (6.55 – 6.64), metatarsus 0.32 – 0.34 / 0.08 – 0.09 (3.78 – 4.00), tarsus 0.87 – 0.89 / 0.06 (14.50 – 14.83). Females: body length 2.19 – 2.27. Pedipalps: trochanter 0.24 – 0.27 / 0.20 – 0.21 (1.20 – 1.29), femur 1.33 – 1.42 / 0.17 – 0.18 (7.82 – 7.89), patella 0.46 – 0.51 / 0.20 – 0.22 (2.30 – 2.32), chela 1.89 – 2.08 / 0.26 – 0.28 (7.27 – 7.43), hand 0.75 – 0.82 / 0.26 – 0.28 (2.88 – 2.93), movable chelal finger length 1.13 – 1.24. Chelicera 0.76 – 0.83 / 0.33 – 0.34 (2.30 – 2.44), movable finger length 0.41 – 0.45. Carapace 0.64 / 0.64 – 0.72 (0.89 – 1.00). Leg Ⅰ: trochanter 0.18 – 0.19 / 0.16 (1.13 – 1.19), femur 0.69 – 0.80 / 0.09 (7.67 – 8.89), patella 0.39 – 0.43 / 0.08 (4.88 – 5.38), tibia 0.32 – 0.36 / 0.06 – 0.07 (5.14 – 5.33), tarsus 0.79 – 0.86 / 0.06 (13.17 – 14.33). Leg IV: trochanter 0.28 – 0.30 / 0.16 (1.75 – 1.88), femoropatella 1.03 – 1.11 / 0.23 – 0.24 (4.48 – 4.63), tibia 0.69 – 0.75 / 0.11 – 0.12 (6.25 – 6.27), metatarsus 0.32 – 0.37 / 0.08 (4.00 – 4.63), tarsus 0.85 – 0.97 / 0.06 (14.17 – 16.17).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF9FFFAEFF053F79E3C23D46.taxon	distribution	Distribution. Known only from the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF90FFABFF053E97E3C23BF6.taxon	description	Figs 6 – 9	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF90FFABFF053E97E3C23BF6.taxon	materials_examined	Type material. Holotype ♀ (Ps. - MHBU-GZXF- 20 - 02 - 01): China, Guizhou Province, Xifeng County, Wenquan Town, Wenquan Village, Guanniu Cave, under the detritus in the deep zone [27 ° 13 ' 24.00 ″ N, 106 ° 52 ' 18.00 ″ E], 853 m a. s. l., 15 August 2020, Zegang Feng, Hongru Xu & Yanmeng Hou leg. Paratype: 1 ♀ (Ps. - MSWU-GZXF- 20 - 02 - 02), with the same data as the holotype.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF90FFABFF053E97E3C23BF6.taxon	etymology	Etymology. Named after the type locality, Guanniu Cave.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF90FFABFF053E97E3C23BF6.taxon	diagnosis	Diagnosis (♀). Moderately sized troglomorphic species with elongated appendages; carapace without eyes or eyespots; anterior margin of carapace thin, finely denticulated, epistome pointed and small, triangular; posterior margin of carapace with two setae; tergites Ⅰ – IV each with two setae. Pedipalps slender, femur 8.19 – 8.47 times longer than broad; chela 6.86 – 7.03 times longer than broad; chelal fingers with intercalary teeth; chelal fingers markedly curved in dorsal view; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF90FFABFF053E97E3C23BF6.taxon	description	Description. Females (holotype and paratype), male unknown (Figs 6 D, 7 – 9). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 8 C, 9 A): carapace 0.95 – 0.97 times longer than broad, gently narrowed posteriorly; surface smooth, without furrows; no traces of eyes; anterior margin slightly serrate; epistome pointed and small, triangular; with 18 setae arranged s 4 s: 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. Chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 5; manducatory process with two acuminate distal setae, anterior seta less than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with 8 – 9 terminally indented coxal spines on each side, set as an oblique and arc row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 9 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 8 D – E, 9 B): large, about as long as carapace, 2.48 – 2.50 times longer than broad; five setae (right chelicera with six setae) and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 11 – 12 teeth, distal one largest; movable finger with 15 – 17 retrorse contiguous small teeth; galea absent (Fig. 9 B). Serrula exterior with 21 – 23 blades and serrula interior with 13 – 14 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. 9 D). Pedipalp (Figs 8 A – B, G, 9 E – G): long and slender, trochanter 1.23 – 1.33, femur 8.19 – 8.47, patella 2.39 – 2.52, chela 6.86 – 7.03, hand 2.57 – 2.62 times longer than broad; femur 2.47 – 2.62 times longer than patella; movable chelal finger 1.65 – 1.67 times longer than hand and 0.62 times longer than chela. Setae generally long and acuminate; one distal lyrifissure present on patella (Figs 8 G, 9 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized, with weak granulation dorsally at base of fixed chelal finger. 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 forming an oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb situated midway between b and st; b and t situated subdistally, t situated at the same level as it and distal to b; est situated distal to b (Fig. 9 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, heterodentate, spaced regularly along the margin, larger teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 33 macrodenticles, slightly retrorse and pointed, plus 25 – 27 intercalary microdenticles, 58 – 60 in total; movable chelal finger with 29 macrodenticles (slightly smaller than teeth on fixed chelal finger), slightly retrorse and pointed, plus 25 intercalary microdenticles and 6 – 7 vestigial, rounded and contiguous basal teeth, 60 – 61 in total (Fig. 9 F). Chelal fingers markedly curved in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 8 B, 9 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 2: 2: 2: 2: 4: 4: 4: 4: 5: 2: T 2 T: 0, tergite IX with an unpaired median seta. Sternal chaetotaxy IV – XII: 11 – 14: 8 – 9: 7: 7: 7 – 8: 7: 7: 0: 2. Anterior genital operculum with 10 – 11 setae, posterior margin with 12 – 13 marginal setae, 23 in total (Fig. 8 F). Legs (Fig. 9 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of femur Ⅰ, IV and patella IV. Femur of leg Ⅰ 1.91 – 1.95 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.50 – 2.54 times longer than tibia. Femoropatella of leg IV 4.32 – 4.76 times longer than deep; tibia 6.18 – 7.00 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 4.22 – 4.63 times longer than deep (TS = 0.26 – 0.27), tarsus 14.57 – 15.67 times longer than deep and 2.54 – 2.68 times longer than metatarsus (TS = 0.30 – 0.31). Arolium slightly shorter than the claws, not divided; claws simple. Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Females: body length 2.20 – 2.55. Pedipalps: trochanter 0.27 – 0.28 / 0.21 – 0.22 (1.23 – 1.33), femur 1.31 – 1.44 / 0.16 – 0.17 (8.19 – 8.47), patella 0.53 – 0.55 / 0.21 – 0.23 (2.39 – 2.52), chela 1.92 – 2.04 / 0.28 – 0.29 (6.86 – 7.03), hand 0.72 – 0.76 / 0.28 – 0.29 (2.57 – 2.62), movable chelal finger length 1.19 – 1.27. Chelicera 0.75 – 0.77 / 0.30 – 0.31 (2.48 – 2.50), movable finger length 0.40. Carapace 0.63 – 0.67 / 0.66 – 0.69 (0.95 – 0.97). Leg Ⅰ: trochanter 0.19 – 0.22 / 0.17 (1.12 – 1.29), femur 0.78 – 0.86 / 0.09 – 0.10 (8.60 – 8.67), patella 0.40 – 0.45 / 0.08 – 0.09 (5.00), tibia 0.32 – 0.35 / 0.06 – 0.07 (5.00 – 5.33), tarsus 0.80 – 0.89 / 0.06 – 0.07 (12.17 – 13.33). Leg IV: trochanter 0.30 – 0.31 / 0.17 (1.72 – 1.82), femoropatella 1.08 – 1.19 / 0.25 (4.32 – 4.76), tibia 0.68 – 0.77 / 0.11 (6.18 – 7.00), metatarsus 0.37 – 0.38 / 0.08 – 0.09 (4.22 – 4.63), tarsus 0.94 – 1.02 / 0.06 – 0.07 (14.57 – 15.67).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF90FFABFF053E97E3C23BF6.taxon	distribution	Distribution. Known only from the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF95FFB0FF05394AE2953C0A.taxon	description	Figs 10 – 14	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF95FFB0FF05394AE2953C0A.taxon	materials_examined	Type material. Holotype ♂ (Ps. - MHBU-HBUARA # 2022 - 525 - 01): China, Guizhou Province, Jiangkou County, Taiping Town, Yunshe Village, Xianren Cave, under stones and detritus in deep zone [27 ° 44 ′ 54.92 ″ N, 108 ° 48 ’ 55.66 ″ E], 517 m a. s. l., 15 August 2022, Yanmeng Hou, Lu Zhang, Jianzhou Sun & Wenlong Fan leg. Paratypes: 5 ♂ (Ps. - MHBU-HBUARA # 2022 - 525 - 02 – HBUARA # 2022 - 525 - 06), 10 ♀ (Ps. - MSWU-HBUARA # 2022 - 525 - 07 – HBUARA # 2022 - 525 - 16), all with the same data as the holotype; 3 ♀ (Ps. - MSWU-HBUARA # 2022 - 306 - 01 – HBUARA # 2022 - 306 - 03), Jiangkou County, Nuxi Town, Mengjiatun Village, Shenxian Cave, [27 ° 49 ′ 39.11 ″ N, 108 ° 51 ′ 33.31 ″ E], 452 m a. s. l., 4 July 2022, Yanmeng Hou, Nana Zhan, Long Lin & Jianzhou Sun leg.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF95FFB0FF05394AE2953C0A.taxon	etymology	Etymology. The specific name is derived from a combination of the Latin words “ latus ” and “ pectus ”, and refers to its broad cephalothorax.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF95FFB0FF05394AE2953C0A.taxon	diagnosis	Diagnosis (♂ ♀). Moderately sized troglomorphic species with elongated appendages; carapace with a pair of anterior eyespots only; anterior margin of carapace thin, finely denticulated, epistome obtuse and small, round; posterior margin of carapace with two setae; tergites Ⅰ – II each with four setae. Pedipalps slender, femur 6.92 – 7.23 (♂), 6.80 – 7.31 (♀) times longer than broad; chela 7.33 – 7.67 (♂), 6.71 – 7.50 (♀) times longer than broad; chelal fingers without intercalary teeth but fixed chelal finger with a modified accessory tooth (td) on retrolateral face; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF95FFB0FF05394AE2953C0A.taxon	description	Description. Males (holotype and paratypes) (Figs 12 A, 13 A – F, 14). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 13 C, E, 14 A): carapace 0.96 – 1.02 times longer than broad, gently narrowed posteriorly; surface smooth, without furrows; anterior eyes reduced into eyespots, posterior eyes reduced completely; anterior margin slightly serrate; epistome obtuse and small, round, with two setae flanking base; with 18 setae arranged s 4 s: 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 setae of ocular row, second pair situated lateral to the sole pair of setae of posterior row. Chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 4 – 5, IV 5; manducatory process with two acuminate distal setae, anterior seta more than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with 9 – 11 terminally indented coxal spines on each side, set as an oblique row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 14 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 13 D, 14 B): large, about as long as carapace, 2.26 – 2.30 times longer than broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 14 – 16 teeth, distal one largest; movable finger with 13 retrorse contiguous small teeth; galea absent (Fig. 14 B). Serrula exterior with 20 – 22 blades and serrula interior with 12 – 13 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. 14 D). Pedipalp (Figs 13 A – B, H, 14 E – G): long and slender, trochanter 1.36, femur 6.92 – 7.23, patella 2.27 – 2.43, chela 7.33 – 7.67, hand 2.78 – 2.83 times longer than broad; femur 2.65 – 2.76 times longer than patella; movable chelal finger 1.68 – 1.71 times longer than hand and 0.63 – 0.64 times longer than chela. Setae generally long and acuminate; one distal lyrifissure present on patella (Figs 13 H, 14 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized, with weak granulation dorsally at base of fixed chelal finger and hand. 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 forming a straight oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb closer to st than to b; b and t situated subdistally, t situated distal to it and b; est slightly distal to b (Fig. 14 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, homodentate, spaced regularly along the margin, larger and well-spaced teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 27 – 29 macrodenticles, slightly retrorse and pointed, plus a modified accessory tooth on retrolateral face (td, close to dx), 28 – 30 in total; movable chelal finger with 13 macrodenticles (slightly smaller than teeth on fixed chelal finger), slightly retrorse and pointed, plus 16 – 17 vestigial, rounded and contiguous basal teeth, 29 – 30 in total (Fig. 14 F). Chelal fingers slightly curved in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 13 B, 14 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 4: 4: 4: 4: 4: 4: 4: 4 – 5: 5: 4: T 2 T: 0, tergites VIII and IX each with an unpaired median seta. Sternal chaetotaxy III – XII: 13 – 14: 12 – 15: 9: 9: 9: 9: 10 – 11: 10: 0: 2. Anterior genital operculum with ten setae, genital opening slit-like, with 12 – 14 marginal setae on each side, 36 in total (Fig. 13 F). Legs (Fig. 14 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of femur IV and patella IV. Femur of leg Ⅰ 1.82 – 1.85 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.33 times longer than tibia. Femoropatella of leg IV 3.04 – 3.13 times longer than deep; tibia 5.67 – 5.89 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 3.43 – 3.57 times longer than deep (TS = 0.32 – 0.33), tarsus 12.00 – 12.20 times longer than deep and 2.44 – 2.50 times longer than metatarsus (TS = 0.25 – 0.34). Arolium slightly shorter than the claws, not divided; claws simple. Adult females (paratypes) (Figs 11 D, 12 B, 13 G). Mostly same as males, but a little larger; chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 5; tergal chaetotaxy Ⅰ – XII: 4: 4: 3 – 4: 4: 4: 4 – 5: 4 – 5: 5: 5 – 6: 4: T 2 T: 0; sternal chaetotaxy IV – XII: 11 – 13: 9 – 10: 9: 9: 9 – 10: 10 – 12: 9 – 10: 0: 2; anterior genital operculum with 9 – 10 setae, posterior margin with 12 – 13 marginal setae, 21 – 23 in total; leg IV with a long tactile seta on both tarsal segments: metatarsus 2.88 – 3.57 times longer than deep (TS = 0.30 – 0.38), tarsus 10.33 – 11.80 times longer than deep and 2.48 – 2.81 times longer than metatarsus (TS = 0.27 – 0.32). Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Males: body length 1.71 – 1.88. Pedipalps: trochanter 0.19 / 0.14 (1.36), femur 0.90 – 0.94 / 0.13 (6.92 – 7.63), patella 0.34 / 0.14 – 0.15 (2.27 – 2.43), chela 1.32 – 1.38 / 0.18 (7.33 – 7.67), hand 0.50 – 0.51 / 0.18 (2.78 – 2.83), movable chelal finger length 0.84 – 0.87. Chelicera 0.52 – 0.53 / 0.23 (2.26 – 2.30), movable finger length 0.28 – 0.29. Carapace 0.50 / 0.49 – 0.52 (0.96 – 1.02). Leg Ⅰ: trochanter 0.15 – 0.16 / 0.13 (1.15 – 1.23), femur 0.50 – 0.51 / 0.08 (6.25 – 6.38), patella 0.27 – 0.28 / 0.07 (3.86 – 4.00), tibia 0.24 / 0.05 – 0.06 (4.00 – 4.80), tarsus 0.56 / 0.05 (11.20). Leg IV: trochanter 0.23 – 0.24 / 0.14 – 0.15 (1.60 – 1.64), femoropatella 0.73 – 0.75 / 0.24 (3.04 – 3.13), tibia 0.51 – 0.53 / 0.09 (5.67 – 5.89), metatarsus 0.24 – 0.25 / 0.07 (3.43 – 3.57), tarsus 0.60 – 0.61 / 0.05 (12.00 – 12.20). Females: body length 1.84 – 2.32. Pedipalps: trochanter 0.18 – 0.22 / 0.14 – 0.16 (1.25 – 1.43), femur 0.95 – 1.02 / 0.13 – 0.15 (6.80 – 7.31), patella 0.35 – 0.40 / 0.14 – 0.17 (2.25 – 2.57), chela 1.35 – 1.50 / 0.18 – 0.22 (6.71 – 7.50), hand 0.50 – 0.56 / 0.18 – 0.22 (2.55 – 2.78), movable chelal finger length 0.86 – 0.94. Chelicera 0.53 – 0.62 / 0.24 – 0.29 (2.14 – 2.32), movable finger length 0.28 – 0.33. Carapace 0.50 – 0.57 / 0.52 – 0.61 (0.93 – 0.98). Leg Ⅰ: trochanter 0.14 – 0.16 / 0.13 – 0.14 (1.00 – 1.23), femur 0.51 – 0.57 / 0.08 – 0.09 (6.11 – 7.13), patella 0.26 – 0.30 / 0.07 – 0.08 (3.63 – 3.75), tibia 0.23 – 0.28 / 0.06 (3.83 – 4.67), tarsus 0.55 – 0.65 / 0.05 – 0.06 (10.00 – 11.40). Leg IV: trochanter 0.22 – 0.25 / 0.13 – 0.16 (1.50 – 1.69), femoropatella 0.73 – 0.79 / 0.21 – 0.26 (3.04 – 3.48), tibia 0.51 – 0.56 / 0.09 – 0.11 (5.09 – 5.89), metatarsus 0.21 – 0.26 / 0.07 – 0.08 (2.88 – 3.57), tarsus 0.59 – 0.66 / 0.05 – 0.06 (10.33 – 11.80).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF95FFB0FF05394AE2953C0A.taxon	distribution	Distribution. Known only from the Xianren and Shenxian caves.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF8EFFBDFF053FDBE3C23BCA.taxon	description	Figs 15 – 18	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF8EFFBDFF053FDBE3C23BCA.taxon	materials_examined	Type material. Holotype ♂ (Ps. - MHBU-HBUARA # 2021 - 433 - 01): China, Guizhou Province, Ceheng County, Rongdu Town, Hongbaituo Village, Hongbaituo Cave, under stones in the deep zone [25 ° 4 ′ 42.31 ″ N, 105 ° 43 ′ 3.96 ″ E], 1033 m a. s. l., 10 October 2021, Zegang Feng, Yanmeng Hou, Lu Zhang & Liu Fu leg. Paratype: 1 ♀ (Ps. - MSWU-HBUARA # 2021 - 433 - 02), with the same data as the holotype.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF8EFFBDFF053FDBE3C23BCA.taxon	etymology	Etymology. The specific name is derived from the Latin words “ longus ” and “ dentatus ”, meaning elongate and toothed, respectively, and referring to the elongated intercalary teeth on the fixed chelal finger.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF8EFFBDFF053FDBE3C23BCA.taxon	diagnosis	Diagnosis (♂ ♀). Moderately sized troglomorphic species with elongated appendages; carapace without eyes or eyespots; anterior margin of carapace thin, finely denticulated, epistome small, pointed, triangular; posterior margin of carapace with two setae; tergites III – VII each with four setae. Pedipalps slender, femur 7.15 (♂), 7.42 (♀) times longer than broad; chela robust, 6.65 (♂), 6.63 (♀) times longer than broad; chelal fingers with intercalary teeth; fixed chelal finger with a row of macrodenticles that are distinctly larger than movable chelal finger teeth, pointed and slightly retrorse, fixed chelal finger intercalary teeth almost as large as movable finger teeth; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF8EFFBDFF053FDBE3C23BCA.taxon	description	Description. Male (holotype) (Figs 20 A, 17 A – F, 18). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 17 C, 18 A): carapace 1.00 times longer than broad, squarish, gently narrowed posteriorly; surface smooth, without furrows; no traces of eyes; anterior margin slightly serrate; epistome small, pointed, triangular; with 18 setae arranged s 4 s: 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 setae of ocular row, second pair situated lateral to the sole pair of setae of posterior row. Chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 5; manducatory process with two acuminate distal setae, anterior seta less than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with seven terminally indented coxal spines on each side, set as an oblique row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 18 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 17 D, 18 B): large, about as long as carapace, 2.48 times longer than broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 17 teeth, distal one largest; movable finger with 17 retrorse contiguous small teeth; galea absent (Fig. 18 B). Serrula exterior with 20 blades and serrula interior with 12 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. 18 D). Pedipalp (Figs 17 A – B, E, 18 E – G): long and slender, trochanter 1.07, femur 7.15, patella 2.20, chela 6.65, hand 2.50 times longer than broad; femur 2.82 times longer than patella; movable chelal finger 1.66 times longer than hand and 0.62 times longer than chela. Setae generally long and acuminate; one distal lyrifissure present on patella (Figs 17 E, 18 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger sclerotized, with weak granulation dorsally at base of fixed chelal finger and hand. 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 forming an oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb closer to st than to b; b and t situated subdistally, t situated distal to b and it; est situated at same level as b (Fig. 18 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, heterodentate, spaced regularly along the margin, larger teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 28 macrodenticles, slightly retrorse and pointed, plus 19 intercalary microdenticles, 47 in total; movable chelal finger with 24 macrodenticles (markedly smaller than teeth on fixed chelal finger), slightly retrorse and pointed, plus 12 intercalary microdenticles (extending roughly to the middle of sb and b) and nine vestigial, rounded and contiguous basal teeth, 45 in total (Fig. 18 F). Chelal fingers slightly curved in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 17 B, 18 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 2: 4: 4: 4: 4: 4: 4: 5: 5: 4: T 2 T: 0, tergites VIII and IX each with an unpaired median seta. Sternal chaetotaxy III – XII: 12: 9: 9: 9: 9: 10: 9: 7: 0: 2. Anterior genital operculum with 11 setae, genital opening slit-like, with 13 – 15 marginal setae on each side, 39 in total (Fig. 17 F). Legs (Fig. 18 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of femur IV and patella IV. Femur of leg Ⅰ 1.77 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.46 times longer than tibia. Femoropatella of leg IV 3.48 times longer than deep; tibia 5.67 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 3.71 times longer than deep (TS = 0.35), tarsus 14.00 times longer than deep and 2.69 times longer than metatarsus (TS = 0.23). Arolium slightly shorter than the claws, not divided; claws simple. Adult female (paratype) (Figs 15 D, 16 B, 17 G). Mostly same as male; with same chaetotaxy of coxae as male; tergal chaetotaxy Ⅰ – XII: 4: 3: 4: 4: 4: 4: 4: 4: 5: 4: T 2 T: 0; sternal chaetotaxy IV – XII: 11: 9: 8: 9: 9: 9: 8: 0: 2; anterior genital operculum with ten setae, posterior margin with 12 marginal setae, 22 in total; leg IV with a long tactile seta on both tarsal segments: metatarsus 3.43 times longer than deep (TS = 0.38), tarsus 12.60 times longer than deep and 2.63 times longer than metatarsus (TS = 0.29). Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Male: body length 1.42. Pedipalps: trochanter 0.16 / 0.15 (1.07), femur 0.93 / 0.13 (7.15), patella 0.33 / 0.15 (2.20), chela 1.33 / 0.20 (6.65), hand 0.50 / 0.20 (2.50), movable chelal finger length 0.83. Chelicera 0.57 / 0.23 (2.48), movable finger length 0.30. Carapace 0.49 / 0.49 (1.00). Leg Ⅰ: trochanter 0.15 / 0.14 (1.07), femur 0.53 / 0.07 (7.57), patella 0.30 / 0.06 (5.00), tibia 0.24 / 0.05 (4.80), tarsus 0.59 / 0.05 (11.80). Leg IV: trochanter 0.22 / 0.13 (1.69), femoropatella 0.80 / 0.23 (3.48), tibia 0.51 / 0.09 (5.67), metatarsus 0.26 / 0.07 (3.71), tarsus 0.70 / 0.05 (14.00). Female: body length 1.59. Pedipalps: trochanter 0.18 / 0.14 (1.29), femur 0.89 / 0.12 (7.42), patella 0.30 / 0.15 (2.00), chela 1.26 / 0.19 (6.63), hand 0.49 / 0.19 (2.58), movable chelal finger length 0.76. Chelicera 0.55 / 0.22 (2.50), movable finger length 0.29. Carapace 0.47 / 0.48 (0.98). Leg Ⅰ: trochanter 0.14 / 0.12 (1.17), femur 0.52 / 0.07 (7.43), patella 0.28 / 0.06 (4.67), tibia 0.23 / 0.05 (4.60), tarsus 0.55 / 0.05 (11.00). Leg IV: trochanter 0.22 / 0.14 (1.57), femoropatella 0.71 / 0.20 (3.55), tibia 0.46 / 0.08 (5.75), metatarsus 0.24 / 0.07 (3.43), tarsus 0.63 / 0.05 (12.60).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF8EFFBDFF053FDBE3C23BCA.taxon	distribution	Distribution. Known only from the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF83FFBAFF05391BE3C2385E.taxon	description	Figs 19 – 22	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF83FFBAFF05391BE3C2385E.taxon	materials_examined	Type material. Holotype ♂ (Ps. - MHBU-HBUARA # 2021 - 153 - 01): China, Guizhou Province, Bozhou District, Fengxiang Town, Qingkeng Village, Longyan Cave, under stones in the deep zone [27 ° 37 ′ 49.38 ″ N, 106 ° 30 ′ 6.90 ″ E], 1082 m a. s. l., 6 July 2021, Zegang Feng, Hongru Xu, Liu Fu & Nana Zhan leg. Paratypes: 2 ♂ (Ps. - MSWU-HBUARA # 2021 - 153 - 02 & HBUARA # 2021 - 153 - 03), 1 ♀ (Ps. - MSWU-HBUARA # 2021 - 153 - 04), all with the same data as the holotype.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF83FFBAFF05391BE3C2385E.taxon	etymology	Etymology. Named after the type locality, Longyan Cave.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF83FFBAFF05391BE3C2385E.taxon	diagnosis	Diagnosis (♂ ♀). Moderately sized troglomorphic species with elongated appendages; carapace without eyes or eyespots; anterior margin of carapace thin, finely denticulated, epistome obtuse and small, round; posterior margin of carapace with two setae; tergites Ⅰ – Ⅴ each with four setae. Pedipalps slender, femur 6.79 – 7.50 (♂), 7.07 (♀) times longer than broad; chela 6.63 – 6.95 (♂), 5.75 (♀) times longer than broad; chelal fingers without intercalary teeth but fixed chelal finger with a modified accessory tooth (td) on retrolateral face; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF83FFBAFF05391BE3C2385E.taxon	description	Description. Males (holotype and paratypes) (Figs 19 D, 20 A, 21 A – F, 22). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 21 C, 22 A): carapace 0.94 – 1.04 times longer than broad, gently narrowed posteriorly; surface smooth, without furrows; no traces of eyes; anterior margin slightly serrate; epistome obtuse and small, round; with 18 setae arranged s 4 s: 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 setae of ocular row, second pair situated lateral to the sole pair of setae of posterior row. Chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 5; manducatory process with two acuminate distal setae, anterior seta more than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with 7 – 9 terminally indented coxal spines on each side, set as an oblique row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 22 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 21 D, 22 B): large, about as long as carapace, 2.19 – 2.35 times longer than broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 8 – 10 teeth, distal one largest; movable finger with 13 – 14 retrorse contiguous small teeth; galea represented by a very slight bump on movable finger (Fig. 22 B). Serrula exterior with 19 – 20 blades and serrula interior with 12 – 13 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. 22 D). Pedipalp (Figs 21 A – B, E, 22 E – G): long and slender, trochanter 1.29 – 1.44, femur 6.79 – 7.50, patella 2.21 – 2.50, chela 6.63 – 6.95, hand 2.79 – 2.84 times longer than broad; femur 2.71 – 2.90 times longer than patella; movable chelal finger 1.43 – 1.48 times longer than hand and 0.60 – 0.61 times longer than chela. Setae generally long and acuminate; one distal lyrifissure present on patella (Figs 21 E, 22 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized, with weak granulation dorsally at base of fixed chelal finger and hand. 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 forming a straight oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb situated midway between b and st; b and t situated subdistally, t situated distal to it and b; est situated at same level as b (Fig. 22 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, homodentate, spaced regularly along the margin, larger and well-spaced teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 24 – 25 macrodenticles, slightly retrorse and pointed, plus a modified accessory tooth on retrolateral face (td, close to dx), 25 – 26 in total; movable chelal finger with ten macrodenticles (slightly smaller than teeth on fixed chelal finger), slightly retrorse and pointed, plus 16 – 17 vestigial, rounded and contiguous basal teeth, 26 – 27 in total (Fig. 22 F). Chelal fingers slightly curved in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 21 B, 22 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 4: 4: 4: 4: 4: 4: 4 – 5: 5: 5: 4: T 2 T: 0, tergites VII – IX each with an unpaired median seta. Sternal chaetotaxy III – XII: 14 – 16: 12 – 13: 10: 8 – 9: 9: 9: 9: 9: 0: 2. Anterior genital operculum with 10 – 11 setae, genital opening slit-like, with 12 – 15 marginal setae on each side, 35 – 39 in total (Fig. 21 F). Legs (Fig. 22 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of femur IV and patella IV. Femur of leg Ⅰ 1.96 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.24 – 2.25 times longer than tibia. Femoropatella of leg IV 3.13 – 3.33 times longer than deep; tibia 5.22 – 5.67 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 3.29 – 3.57 times longer than deep (TS = 0.39 – 0.40), tarsus 11.20 – 12.60 times longer than deep and 2.43 – 2.52 times longer than metatarsus (TS = 0.29). Arolium slightly shorter than the claws, not divided; claws simple. Adult female (paratype) (Figs 20 B, 21 G). Mostly same as males, but a little larger; chaetotaxy of coxae: P 3, Ⅰ 3, II 3 – 4, III 5, IV 5; tergal chaetotaxy Ⅰ – XII: 4: 4: 4: 4: 4: 5: 5: 5: 5: 4: T 2 T: 0; sternal chaetotaxy IV – XII: 12: 10: 9: 9: 9: 10: 9: 0: 2; anterior genital operculum with ten setae, posterior margin with 12 marginal setae, 22 in total; tarsal and tibial segments of leg Ⅰ missing; leg IV with a long tactile seta on both tarsal segments: metatarsus 4.50 times longer than deep (TS = 0.41), tarsus 12.80 times longer than deep and 2.37 times longer than metatarsus (TS = 0.31). Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Males: body length 1.76 – 1.95. Pedipalps: trochanter 0.18 – 0.23 / 0.14 – 0.16 (1.29 – 1.44), femur 0.90 – 0.95 / 0.12 – 0.14 (6.79 – 7.50), patella 0.31 – 0.35 / 0.14 (2.21 – 2.50), chela 1.26 – 1.32 / 0.19 (6.63 – 6.95), hand 0.53 – 0.54 / 0.19 (2.79 – 2.84), movable chelal finger length 0.76 – 0.80. Chelicera 0.46 – 0.47 / 0.20 – 0.21 (2.19 – 2.35), movable finger length 0.25. Carapace 0.47 – 0.49 / 0.47 – 0.50 (0.94 – 1.04). Leg Ⅰ: trochanter 0.16 – 0.17 / 0.12 – 0.13 (1.31 – 1.33), femur 0.51 – 0.53 / 0.07 (7.29 – 7.57), patella 0.26 – 0.27 / 0.07 (3.71 – 3.86), tibia 0.24 – 0.25 / 0.05 – 0.06 (4.17 – 4.80), tarsus 0.54 – 0.56 / 0.05 (10.80 – 11.20). Leg IV: trochanter 0.22 – 0.23 / 0.13 – 0.14 (1.57 – 1.77), femoropatella 0.70 – 0.75 / 0.21 – 0.24 (3.13 – 3.33), tibia 0.47 – 0.51 / 0.09 (5.22 – 5.67), metatarsus 0.23 – 0.25 / 0.07 (3.29 – 3.57), tarsus 0.56 – 0.63 / 0.05 (11.20 – 12.60). Female: body length 1.93. Pedipalps: trochanter 0.20 / 0.15 (1.33), femur 0.99 / 0.14 (7.07), patella 0.36 / 0.15 (2.40), chela 1.38 / 0.24 (5.75), hand 0.59 / 0.24 (2.46), movable chelal finger length 0.80. Chelicera 0.53 / 0.23 (2.30), movable finger length 0.29. Carapace 0.51 / 0.51 (1.00). Leg Ⅰ: trochanter 0.17 / 0.14 (1.21), femur 0.59 / 0.08 (7.38), patella 0.28 / 0.07 (4.00). Leg IV: trochanter 0.20 / 0.12 (1.67), femoropatella 0.79 / 0.20 (3.95), tibia 0.54 / 0.09 (6.00), metatarsus 0.27 / 0.06 (4.50), tarsus 0.64 / 0.05 (12.80).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF83FFBAFF05391BE3C2385E.taxon	distribution	Distribution. Known only from the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF84FF86FF053BEFE3C23CA6.taxon	description	Figs 23 – 26	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF84FF86FF053BEFE3C23CA6.taxon	materials_examined	Type material. Holotype ♀ (Ps. - MHBU-GZZA- 20 - 18 - 01): China, Guizhou Province, Zheng’an County, Hexi Town, Maan Village, Pianxiao Cave, under stones in the deep zone [28 ° 24 ′ 37.86 ″ N, 107 ° 26 ′ 31.84 ″ E], 932 m a. s. l., 25 August 2020, Zegang Feng, Hongru Xu & Yanmeng Hou leg. Paratype: 1 ♀ (Ps. - MSWU-GZZA- 20 - 18 - 02), with the same data as the holotype.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF84FF86FF053BEFE3C23CA6.taxon	etymology	Etymology. Named after the village of Maan, near the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF84FF86FF053BEFE3C23CA6.taxon	diagnosis	Diagnosis (♀). Moderately sized troglomorphic species with elongated appendages; carapace without eyes or eyespots; anterior margin of carapace thin, finely denticulated, epistome obtuse and small, round; posterior margin of carapace with two setae; tergites Ⅰ – II each with two setae, tergites III – Ⅴ each with four setae. Pedipalps slender, femur 5.43 – 5.75 times longer than broad; chela 5.84 – 5.88 times longer than broad; chelal fingers without intercalary teeth but fixed chelal finger with a modified accessory tooth (td) on retrolateral face; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF84FF86FF053BEFE3C23CA6.taxon	description	Description. Females (holotype and paratype), male unknown (Figs 23 E, 24 – 26). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 25 C, 26 A): carapace 0.93 – 0.96 times longer than broad, gently narrowed posteriorly; surface smooth, without furrows; no traces of eyes; anterior margin slightly serrate; epistome obtuse and small, round, with two setae flanking base; with 18 setae arranged s 4 s: 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 setae of ocular row, second pair situated lateral to the sole pair of setae of posterior row. Chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 5; manducatory process with two acuminate distal setae, anterior seta more than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with 8 – 9 terminally indented coxal spines on each side, set as an oblique row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 26 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 25 D, 26 B): large, about as long as carapace, 2.14 – 2.17 times longer than broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 11 – 13 teeth, distal one largest; movable finger with 11 – 12 retrorse contiguous small teeth; galea represented by a very slight bump on movable finger (Fig. 26 B). Serrula exterior with 17 – 18 blades and serrula interior with 13 – 14 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. 26 D). Pedipalp (Figs 25 A – B, F, 26 E – G): long and slender, trochanter 1.18 – 1.38, femur 5.43 – 5.75, patella 2.00 – 2.08, chela 5.84 – 5.88, hand 2.29 – 2.32 times longer than broad; femur 2.71 – 2.76 times longer than patella; movable chelal finger 1.55 – 1.56 times longer than hand and 0.61 times longer than chela. Setae generally long and acuminate; one distal lyrifissure present on patella (Figs 25 F, 26 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized, with weak granulation dorsally at base of fixed chelal finger and hand. 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 forming an oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb closer to st than to b; b and t situated subdistally, t situated distal to b; it and est situated between t and b (Fig. 26 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, homodentate, spaced regularly along the margin, larger and well-spaced teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 25 macrodenticles, slightly retrorse and pointed, plus a modified accessory tooth on retrolateral face (td, close to dx), 26 in total; movable chelal finger with 11 macrodenticles (slightly smaller than teeth on fixed chelal finger), slightly retrorse and pointed, plus 14 – 15 vestigial, rounded and contiguous basal teeth, 25 – 26 in total (Fig. 26 F). Chelal fingers straight in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 25 B, 26 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 2: 2: 4: 4: 4: 4 – 5: 5: 5 – 6: 5 – 6: 4: T 2 T: 0. Sternal chaetotaxy IV – XII: 13 – 14: 9 – 10: 8: 9 – 10: 9: 10 – 12: 10 – 11: 0: 2. Anterior genital operculum with ten setae, posterior margin with 14 – 15 marginal setae, 24 – 25 in total (Fig. 25 E). Legs (Fig. 26 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of femur IV and patella IV. Femur of leg Ⅰ 2.00 – 2.06 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.35 – 2.37 times longer than tibia. Femoropatella of leg IV 2.80 – 2.94 times longer than deep; tibia 4.63 – 5.00 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 3.00 times longer than deep (TS = 0.33 – 0.39), tarsus 10.00 – 11.50 times longer than deep and 2.22 – 2.56 times longer than metatarsus (TS = 0.30 – 0.35). Arolium slightly shorter than the claws, not divided; claws simple. Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Females: body length 1.64 – 1.83. Pedipalps: trochanter 0.13 – 0.18 / 0.11 – 0.13 (1.18 – 1.38), femur 0.69 – 0.76 / 0.12 – 0.14 (5.43 – 5.75), patella 0.25 – 0.28 / 0.12 – 0.14 (2.00 – 2.08), chela 1.00 – 1.11 / 0.17 – 0.19 (5.84 – 5.88), hand 0.39 – 0.44 / 0.17 – 0.19 (2.29 – 2.32), movable chelal finger length 0.61 – 0.68. Chelicera 0.45 – 0.50 / 0.21 – 0.23 (2.14 – 2.17), movable finger length 0.24 – 0.26. Carapace 0.40 – 0.47 / 0.43 – 0.49 (0.93 – 0.96). Leg Ⅰ: trochanter 0.11 / 0.10 – 0.11 (1.00 – 1.10), femur 0.37 – 0.40 / 0.06 – 0.07 (5.71 – 6.17), patella 0.18 – 0.20 / 0.06 (3.00 – 3.33), tibia 0.17 – 0.19 / 0.04 (4.25 – 4.75), tarsus 0.40 – 0.45 / 0.04 (10.00 – 11.25). Leg IV: trochanter 0.17 – 0.19 / 0.11 – 0.12 (1.56), femoropatella 0.50 – 0.56 / 0.17 – 0.20 (2.80 – 2.94), tibia 0.37 – 0.40 / 0.08 (4.63 – 5.00), metatarsus 0.18 / 0.06 (3.00), tarsus 0.40 – 0.46 / 0.04 (10.00 – 11.50).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFF84FF86FF053BEFE3C23CA6.taxon	distribution	Distribution. Known only from the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB8FF83FF053FB7E3C23D9A.taxon	description	Figs 27 – 30	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB8FF83FF053FB7E3C23D9A.taxon	materials_examined	Type material. Holotype ♂ (Ps. - MHBU-GZWC- 20 - 16 - 01): China, Guizhou Province, Wuchuan County, Duru sub-district, Mawang Cave, under stones in the deep zone [28 ° 31 ′ 44.41 ″ N, 107 ° 52 ′ 57.64 ″ E], 706 m a. s. l., 24 August 2020, Zegang Feng, Hongru Xu & Yanmeng Hou leg. Paratypes: 8 ♂ (Ps. - MHBU-GZWC- 20 - 16 - 02 – GZWC- 20 - 16 - 09), 2 ♀ (Ps. - MSWU-GZWC- 20 - 16 - 10 & GZWC- 20 - 16 - 11), all with the same data as the holotype.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB8FF83FF053FB7E3C23D9A.taxon	etymology	Etymology. Named after the type locality, Mawang Cave.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB8FF83FF053FB7E3C23D9A.taxon	diagnosis	Diagnosis (♂ ♀). Moderately sized troglomorphic species with elongated appendages; carapace without eyes or eyespots; anterior margin of carapace thin, finely denticulated, epistome obtuse and small, round; posterior margin of carapace with two setae; tergites Ⅰ – Ⅴ each with four setae. Pedipalps slender, femur 7.18 – 7.40 (♂), 6.67 – 7.27 (♀) times longer than broad; chela 6.87 – 6.94 (♂), 6.22 – 6.33 (♀) times longer than broad; chelal fingers without intercalary teeth and fixed chelal finger with a modified accessory tooth (td) on retrolateral face; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB8FF83FF053FB7E3C23D9A.taxon	description	Description. Males (holotype and paratypes) (Figs 27 D, 28 A, 29 A – F, 30). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 29 C, 30 A): carapace 1.07 – 1.08 times longer than broad, gently narrowed posteriorly; surface smooth, without furrows; no traces of eyes; anterior margin slightly serrate; epistome obtuse and small, round, with two setae flanking base; with 18 setae arranged s 4 s: 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, the second situated exterior to the sole pair of setae of posterior row. Chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 4 – 5; manducatory process with two acuminate distal setae, anterior seta more than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with nine terminally indented coxal spines on each side, set as an oblique and arc row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 30 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 29 D, 30 B): large, about as long as carapace, 2.17 – 2.24 times longer than broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 10 – 11 teeth, distal one largest; movable finger with 9 – 11 retrorse contiguous small teeth; galea represented by a very slight bump on movable finger (Fig. 30 B). Serrula exterior with 19 – 20 blades and serrula interior with 11 – 12 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. 30 D). Pedipalp (Figs 29 A – B, E, 30 E – G): long and slender, trochanter 1.18 – 1.33, femur 7.18 – 7.40, patella 2.25 – 2.36, chela 6.87 – 6.94, hand 2.80 – 2.81 times longer than broad; femur 2.85 – 2.93 times longer than patella; movable chelal finger 1.49 – 1.50 times longer than hand and 0.60 – 0.61 times longer than chela. Setae generally long and acuminate; one distal lyrifissures present on patella (Figs 29 E, 30 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized, with weak granulation dorsally at base of fixed chelal finger and hand. 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 forming a straight oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb closer to st than to b; b and t situated subdistally, t situated distal to b; it and est situated between t and b (Fig. 30 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, homodentate, spaced regularly along the margin, larger and well-spaced teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 25 – 27 macrodenticles, slightly retrorse and pointed, plus a modified accessory tooth on retrolateral face (td, close to dx), 26 – 28 in total; movable chelal finger with ten macrodenticles (slightly smaller than teeth on fixed chelal finger), slightly retrorse and pointed, plus 14 – 15 vestigial, rounded and contiguous basal teeth, 24 – 25 in total (Fig. 30 F). Chelal fingers slightly curved in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 29 B, 30 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 4: 4: 4: 4: 4: 4: 5: 5: 5: 4 – 5: T 2 T: 0, tergites VII – IX each with an unpaired median seta. Sternal chaetotaxy III – XII: 13 – 15: 14: 9 – 10: 10: 9 – 10: 11: 10 – 12: 8 – 10: 0: 2. Anterior genital operculum with 12 setae, genital opening slit-like, with 11 – 14 marginal setae on each side, 35 – 39 in total (Fig. 29 F). Legs (Fig. 30 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of femur IV and patella IV. Femur of leg Ⅰ 2.00 – 2.16 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.45 – 2.61 times longer than tibia. Femoropatella of leg IV 2.90 – 3.05 times longer than deep; tibia 5.38 – 6.00 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 3.00 – 3.33 times longer than deep (TS = 0.40 – 0.44), tarsus 10.40 – 12.00 times longer than deep and 2.60 – 2.67 times longer than metatarsus (TS = 0.29 – 0.31). Arolium slightly shorter than the claws, not divided; claws simple. Adult females (paratypes) (Figs 28 B, 29 G). Mostly same as males, but a little larger; chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 5 – 6; tergal chaetotaxy Ⅰ – XII: 4: 4: 4: 4: 4: 4 – 5: 5: 5: 5: 4 – 5: T 2 T: 0; sternal chaetotaxy IV – XII: 12 – 13: 9 – 11: 10: 9: 9 – 10: 11: 8 – 10: 0: 2; anterior genital operculum with ten setae, posterior margin with 11 – 13 marginal setae, 21 – 23 in total; leg IV with a long tactile seta on both tarsal segments: metatarsus 3.50 times longer than deep (TS = 0.33 – 0.38), tarsus 12.25 – 12.75 times longer than deep and 2.33 – 2.43 times longer than metatarsus (TS = 0.29 – 0.31). Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Males: body length 1.59 – 1.66. Pedipalps: trochanter 0.13 – 0.16 / 0.11 – 0.12 (1.18 – 1.33), femur 0.74 – 0.79 / 0.10 – 0.11 (7.18 – 7.40), patella 0.26 – 0.27 / 0.11 – 0.12 (2.25 – 2.36), chela 1.03 – 1.11 / 0.15 – 0.16 (6.87 – 6.94), hand 0.42 – 0.45 / 0.15 – 0.16 (2.80 – 2.81), movable chelal finger length 0.63 – 0.67. Chelicera 0.38 – 0.39 / 0.17 – 0.18 (2.17 – 2.24), movable finger length 0.20. Carapace 0.42 – 0.44 / 0.39 – 0.41 (1.07 – 1.08). Leg Ⅰ: trochanter 0.10 – 0.12 / 0.09 – 0.11 (1.09 – 1.11), femur 0.41 – 0.44 / 0.06 – 0.07 (6.29 – 6.83), patella 0.19 – 0.22 / 0.06 (3.17 – 3.67), tibia 0.18 – 0.20 / 0.04 – 0.05 (4.00 – 4.50), tarsus 0.47 – 0.49 / 0.04 – 0.05 (9.80 – 11.75). Leg IV: trochanter 0.18 – 0.19 / 0.13 (1.38 – 1.46), femoropatella 0.58 – 0.61 / 0.19 – 0.21 (2.90 – 3.05), tibia 0.42 – 0.43 / 0.07 – 0.08 (5.38 – 6.00), metatarsus 0.18 – 0.20 / 0.06 (3.00 – 3.33), tarsus 0.48 – 0.52 / 0.04 – 0.05 (10.40 – 12.00). Females: body length 1.64 – 1.73. Pedipalps: trochanter 0.15 – 0.16 / 0.12 (1.25 – 1.33), femur 0.80 / 0.11 – 0.12 (6.67 – 7.27), patella 0.28 – 0.29 / 0.12 – 0.13 (2.23 – 2.33), chela 1.12 – 1.14 / 0.18 (6.22 – 6.33), hand 0.45 / 0.18 (2.50), movable chelal finger length 0.69. Chelicera 0.41 – 0.42 / 0.19 – 0.20 (2.05 – 2.21), movable finger length 0.21 – 0.22. Carapace 0.42 – 0.44 / 0.43 – 0.47 (0.94 – 0.98). Leg Ⅰ: trochanter 0.11 – 0.13 / 0.11 – 0.12 (0.92 – 1.18), femur 0.42 – 0.43 / 0.07 (6.00 – 6.14), patella 0.21 – 0.22 / 0.06 (3.50 – 3.67), tibia 0.20 / 0.05 (4.00), tarsus 0.48 – 0.49 / 0.05 (9.60 – 10.80). Leg IV: trochanter 0.19 – 0.20 / 0.11 – 0.13 (1.54 – 1.73), femoropatella 0.59 – 0.61 / 0.18 – 0.19 (3.21 – 3.28), tibia 0.40 – 0.43 / 0.08 (5.00 – 5.38), metatarsus 0.21 / 0.06 (3.50), tarsus 0.49 – 0.51 / 0.04 (12.25 – 12.75).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB8FF83FF053FB7E3C23D9A.taxon	distribution	Distribution. Known only from the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFBDFF89FF053EABE29538F6.taxon	description	Figs 31 – 35	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFBDFF89FF053EABE29538F6.taxon	materials_examined	Type material. Holotype ♂ (Ps. - MHBU-HBUARA # 2021 - 423 - 01): China, Guizhou Province, Weining County, Yangjie Town, Songshan Village, Yuqiyan Cave, under stones in the deep zone [26 ° 59 ′ 21.87 ″ N, 104 ° 20 ′ 23.68 ″ E], 2143 m a. s. l., 4 October 2021, Zegang Feng, Yanmeng Hou, Lu Zhang & Liu Fu leg. Paratypes: 4 ♀ (Ps. - MHBU-HBUARA # 2021 - 423 - 02 – HBUARA # 2021 - 423 - 05), all with the same data as the holotype; 6 ♀ (Ps. - MSWU-HBUARA # 2021 - 425 - 01 – HBUARA # 2021 - 425 - 06), Songshan Village, unnamed cave, [26 ° 59 ′ 14.67 ″ N, 104 ° 20 ′ 33.35 ″ E], 2165 m a. s. l., with the same collection date and collectors as the holotype; 1 ♂ (Ps. - MSWU-HBUARA # 2022 - 495 - 01), 4 ♀ (Ps. - MSWU-HBUARA # 2022 - 495 - 02 – HBUARA # 2022 - 495 - 05), Songshan Village, unnamed cave, 31 July 2022, Yanmeng Hou, Lu Zhang, Jianzhou Sun & Wenlong Fan leg.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFBDFF89FF053EABE29538F6.taxon	etymology	Etymology. The specific name is derived from the Latin adjective “ nigriculus ”, meaning blackish, which refers to the black tergites.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFBDFF89FF053EABE29538F6.taxon	diagnosis	Diagnosis (♂ ♀). Moderately sized troglomorphic species with elongated appendages; carapace without eyes or eyespots; anterior margin of carapace thin, finely denticulated, epistome small and pointed, triangular; posterior margin of carapace with two setae; tergites Ⅰ – II each with two setae. Pedipalps slender, femur 8.93 – 9.00 (♂), 8.24 – 8.67 (♀) times longer than broad; chela 8.00 – 8.14 (♂), 7.25 – 7.68 (♀) times longer than broad; chelal fingers without intercalary teeth but fixed chelal finger with a modified accessory tooth (td) on retrolateral face; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFBDFF89FF053EABE29538F6.taxon	description	Description. Males (holotype and paratype) (Figs 31 D, 33 A, 34 A – F, 35). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 34 C, 35 A): carapace 0.97 – 1.05 times longer than broad, gently narrowed posteriorly; surface smooth, without furrows; no traces of eyes; anterior margin slightly serrate; epistome small and pointed, triangular, with two setae flanking base; with 18 setae arranged s 4 s: 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, the second situated exterior to the sole pair of setae of posterior row. Chaetotaxy of coxae: P 3, Ⅰ 3, II 3 – 4, III 5, IV 5; manducatory process with two acuminate distal setae, anterior seta less than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with 13 – 15 terminally indented coxal spines on each side, set as an oblique and arc row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 35 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 34 D, 35 B): large, about as long as carapace, 2.43 – 2.48 times longer than broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 19 – 20 teeth, distal one largest; movable finger with 21 – 23 retrorse contiguous small teeth; galea absent (Fig. 35 B). Serrula exterior with 23 blades and serrula interior with 12 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. 35 D). Pedipalp (Figs 34 A – B, E, 35 E – G): long and slender, trochanter 1.32 – 1.44, femur 8.93 – 9.00, patella 2.56 – 2.67, chela 8.00 – 8.14, hand 3.33 – 3.41 times longer than broad; femur 2.81 – 3.05 times longer than patella; movable chelal finger 1.37 – 1.39 times longer than hand and 0.58 times longer than chela. Setae generally long and acuminate; one distal lyrifissures present on patella (Figs 34 E, 35 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized, with weak granulation dorsally at base of fixed chelal finger and hand. 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 forming a straight oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb closer to st than to b; b and t situated subdistally, t situated distal to b; b distal to est; it situated between t and b (Fig. 35 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, homodentate, spaced regularly along the margin, larger and well-spaced teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 29 – 30 macrodenticles, slightly retrorse and pointed, plus a modified accessory tooth on retrolateral face (td, close to dx), 30 – 31 in total; movable chelal finger with 20 – 21 macrodenticles (smaller than teeth on fixed chelal finger), slightly retrorse and pointed, plus 7 – 9 vestigial, rounded and contiguous basal teeth, 28 – 29 in total (Fig. 35 F). Chelal fingers slightly curved in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 34 B, 35 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 2: 2: 2 – 4: 4: 4: 4 – 6: 4 – 5: 5: 5: 2: T 2 T: 0, tergites VIII and IX each with an unpaired median seta. Sternal chaetotaxy III – XII: 13 – 14: 11 – 12: 8 – 9: 7 – 8: 7 – 9: 8 – 9: 7 – 9: 7 – 8: 0: 2. Anterior genital operculum with 11 setae, genital opening slit-like, with 12 – 15 marginal setae on each side, 36 – 39 in total (Fig. 35 F). Legs (Fig. 35 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of femur IV and patella IV. Femur of leg Ⅰ 1.83 – 1.92 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.59 times longer than tibia. Femoropatella of leg IV 4.68 – 4.95 times longer than deep; tibia 6.90 – 7.00 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 3.88 – 4.14 times longer than deep (TS = 0.26 – 0.28), tarsus 14.83 – 15.40 times longer than deep and 2.66 – 2.87 times longer than metatarsus (TS = 0.34 – 0.36). Arolium slightly shorter than the claws, not divided; claws simple. Adult females (paratypes) (Figs 31 E, 33 B, 34 G). Mostly same as males, but a little larger; chaetotaxy of coxae: P 3, Ⅰ 3 – 4, II 4, III 5, IV 5; tergal chaetotaxy Ⅰ – XII: 2: 2: 2 – 4: 3 – 4: 4: 4: 4: 5: 5: 2: T 2 T: 0; sternal chaetotaxy IV – XII: 12 – 14: 8 – 10: 8 – 10: 8 – 9: 8 – 9: 7 – 9: 7 – 8: 0: 2; anterior genital operculum with 10 – 12 setae, posterior margin with 13 – 15 marginal setae, 24 – 26 in total; leg IV with a long tactile seta on both tarsal segments: metatarsus 3.63 – 3.88 times longer than deep (TS = 0.23 – 0.31), tarsus 14.50 – 17.20 times longer than deep and 2.77 – 2.97 times longer than metatarsus (TS = 0.28 – 0.34). Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Males: body length 2.00. Pedipalps: trochanter 0.23 – 0.25 / 0.16 – 0.19 (1.32 – 1.44), femur 1.25 – 1.35 / 0.14 – 0.15 (8.93 – 9.00), patella 0.41 – 0.48 / 0.16 – 0.18 (2.56 – 2.67), chela 1.79 – 1.92 / 0.22 – 0.24 (8.00 – 8.14), hand 0.75 – 0.80 / 0.22 – 0.24 (3.33 – 3.41), movable chelal finger length 1.03 – 1.11. Chelicera 0.67 – 0.73 / 0.27 – 0.30 (2.43 – 2.48), movable finger length 0.37 – 0.40. Carapace 0.56 – 0.64 / 0.58 – 0.61 (0.97 – 1.05). Leg Ⅰ: trochanter 0.16 – 0.20 / 0.13 – 0.16 (1.23 – 1.25), femur 0.69 – 0.73 / 0.08 – 0.09 (8.11 – 8.63), patella 0.36 – 0.40 / 0.07 – 0.08 (5.00 – 5.14), tibia 0.29 – 0.32 / 0.06 – 0.07 (4.57 – 4.83), tarsus 0.75 – 0.83 / 0.06 (12.50 – 13.83). Leg IV: trochanter 0.26 – 0.29 / 0.15 – 0.16 (1.73 – 1.81), femoropatella 0.94 – 1.03 / 0.19 – 0.22 (4.68 – 4.95), tibia 0.63 – 0.69 / 0.09 – 0.10 (6.90 – 7.00), metatarsus 0.29 – 0.31 / 0.07 – 0.08 (3.88 – 4.14), tarsus 0.77 – 0.89 / 0.05 – 0.06 (14.83 – 15.40). Females: body length 2.17 – 2.74. Pedipalps: trochanter 0.23 – 0.26 / 0.18 – 0.21 (1.19 – 1.37), femur 1.30 – 1.40 / 0.15 – 0.17 (8.24 – 8.67), patella 0.44 – 0.48 / 0.18 – 0.20 (2.40 – 2.67), chela 1.84 – 2.03 / 0.24 – 0.28 (7.25 – 7.68), hand 0.78 – 0.84 / 0.24 – 0.28 (3.00 – 3.25), movable chelal finger length 1.06 – 1.20. Chelicera 0.73 – 0.81 / 0.29 – 0.33 (2.38 – 2.52), movable finger length 0.40 – 0.44. Carapace 0.61 – 0.72 / 0.64 – 0.68 (0.93 – 1.06). Leg Ⅰ: trochanter 0.18 – 0.22 / 0.15 – 0.18 (1.19 – 1.25), femur 0.71 – 0.78 / 0.08 – 0.10 (7.80 – 9.13), patella 0.37 – 0.42 / 0.08 – 0.10 (4.67 – 5.29), tibia 0.30 – 0.34 / 0.06 – 0.07 (4.86 – 5.33), tarsus 0.77 – 0.89 / 0.06 – 0.07 (12.71 – 13.33). Leg IV: trochanter 0.27 – 0.31 / 0.15 – 0.17 (1.71 – 1.94), femoropatella 1.00 – 1.10 / 0.20 – 0.22 (4.59 – 5.00), tibia 0.65 – 0.71 / 0.10 – 0.11 (6.18 – 6.50), metatarsus 0.29 – 0.34 / 0.08 – 0.09 (3.63 – 3.88), tarsus 0.83 – 0.95 / 0.05 – 0.06 (14.50 – 17.20).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFBDFF89FF053EABE29538F6.taxon	distribution	Distribution. Known only from the Yuqiyan and unnamed caves.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB7FF95FF053847E3C23EAE.taxon	description	Figs 36 – 39	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB7FF95FF053847E3C23EAE.taxon	materials_examined	Type material. Holotype ♂ (Ps. - MHBU-GZC 190806 - 01): China, Guizhou Province, Shuicheng District, Duge Town, Hongguang Village, Tuoluodadong Cave, under stones in the deep zone [26 ° 18 ′ 29.76 ″ N, 104 ° 41 ′ 44.11 ″ E], 1435 m a. s. l., 6 August 2019, Zegang Feng, Zhaoyi Li & Chen Zhang leg. Paratypes: 1 ♂ (Ps. - MHBU-GZC 190806 - 02), 6 ♀ (Ps. - MSWU-GZC 190806 - 03 – GZC 190806 - 08), all with the same data as the holotype.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB7FF95FF053847E3C23EAE.taxon	etymology	Etymology. Named after the type locality, Tuoluodadong Cave.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB7FF95FF053847E3C23EAE.taxon	diagnosis	Diagnosis (♂ ♀). Small-sized troglomorphic species with elongated appendages; carapace without eyes or eyespots; anterior margin of carapace thin and finely denticulated, epistome obtuse and small, round; posterior margin of the carapace with two setae; tergites Ⅰ – II each with two setae, tergites III – IV each with four setae. Pedipalps slender, femur 6.67 – 6.89 (♂), 6.45 – 6.80 (♀) times longer than broad; chela 5.87 – 6.21 (♂), 5.76 – 5.88 (♀) times longer than broad; chelal fingers without intercalary teeth but fixed chelal finger with a modified accessory tooth (td) on retrolateral face; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB7FF95FF053847E3C23EAE.taxon	description	Description. Males (holotype and paratype) (Figs 37 A, 38 A – F, 39). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 38 C, 39 A): carapace 1.06 – 1.09 times longer than broad, markedly narrowed posteriorly; surface smooth, without furrows; no traces of eyes; anterior margin slightly serrate; epistome obtuse and small, round, with two setae flanking base; with 18 setae arranged s 4 s: 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, the second situated exterior to the sole pair of setae of posterior row. Chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 5; manducatory process with two acuminate distal setae, anterior seta more than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with 8 – 10 terminally indented coxal spines on each side, set as an oblique and arc row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 39 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 38 D, 39 B): large, about as long as carapace, 2.13 – 2.33 times longer than broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with ten teeth, distal one largest; movable finger with 8 – 9 retrorse contiguous small teeth; galea absent (Fig. 39 B). Serrula exterior with 16 – 17 blades and serrula interior with 10 – 11 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. 39 D). Pedipalp (Figs 38 A – B, E, 39 E – G): long and slender, trochanter 1.33 – 1.50, femur 6.67 – 6.89, patella 2.20 – 2.33, chela 5.87 – 6.21, hand 2.27 – 2.43 times longer than broad; femur 2.82 – 2.86 times longer than patella; movable chelal finger 1.56 – 1.59 times longer than hand and 0.60 – 0.62 times longer than chela. Setae generally long and acuminate; one distal lyrifissure present on patella (Figs 38 E, 39 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized, with weak granulation dorsally at base of fixed chelal finger and hand. 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 forming a straight oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb closer to st than to b; b and t situated subdistally, t situated distal to b; it and est situated between b and t (Fig. 39 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, homodentate, spaced regularly along the margin, larger and well-spaced teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 26 – 27 macrodenticles, slightly retrorse and pointed, plus a modified accessory tooth on retrolateral face (td, near tip), 27 – 28 in total; movable chelal finger with 11 macrodenticles (slightly smaller than teeth on fixed chelal finger), slightly retrorse and pointed, plus 16 – 17 vestigial, rounded and contiguous basal teeth, 27 – 28 in total (Fig. 39 F). Chelal fingers slightly curved in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 38 B, 39 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 2: 2: 4: 4: 4: 4: 4 – 6: 5 – 6: 5 – 6: 4 – 5: T 2 T: 0. Sternal chaetotaxy III – XII: 12 – 14: 14: 8 – 10: 8 – 9: 8 – 10: 8 – 10: 9 – 11: 9: 0: 2. Anterior genital operculum with 11 – 12 setae, genital opening slit-like, with 13 – 16 marginal setae on each side, 38 – 43 in total (Fig. 38 F). Legs (Fig. 39 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of femur IV and patella IV. Femur of leg Ⅰ 1.94 – 2.06 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.38 – 2.47 times longer than tibia. Femoropatella of leg IV 2.33 – 2.59 times longer than deep; tibia 4.71 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 3.20 times longer than deep (TS = 0.38), tarsus 9.25 – 9.50 times longer than deep and 2.31 – 2.38 times longer than metatarsus (TS = 0.27 – 0.29). Arolium slightly shorter than the claws, not divided; claws simple. Adult females (paratypes) (Figs 36 C, 37 B, 38 G). Mostly same as males, but a little larger on average; with same coxal chaetotaxy as males; tergal chaetotaxy Ⅰ – XII: 2: 2: 4: 4: 5 – 6: 5 – 6: 5 – 6: 6 – 7: 6 – 7: 3 – 4: T 2 T: 0; sternal chaetotaxy IV – XII: 11 – 12: 9 – 11: 8 – 10: 9 – 11: 10 – 12: 11: 11: 0: 2; anterior genital operculum with 12 setae, posterior margin with 12 – 13 marginal setae, 24 – 25 in total; leg IV with a long tactile seta on both tarsal segments: metatarsus 3.00 – 3.40 times longer than deep (TS = 0.33 – 0.35), tarsus 10.00 – 10.25 times longer than deep and 2.28 – 2.35 times longer than metatarsus (TS = 0.24 – 0.28). Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Males: body length 1.14 – 1.28. Pedipalps: trochanter 0.12 – 0.15 / 0.09 – 0.10 (1.33 – 1.50), femur 0.60 – 0.62 / 0.09 (6.67 – 6.89), patella 0.21 – 0.22 / 0.09 – 0.10 (2.20 – 2.33), chela 0.87 – 0.88 / 0.14 – 0.15 (5.87 – 6.21), hand 0.34 / 0.14 – 0.15 (2.27 – 2.43), movable chelal finger length 0.53 – 0.54. Chelicera 0.34 – 0.35 / 0.15 – 0.16 (2.13 – 2.33), movable finger length 0.18 – 0.19. Carapace 0.37 – 0.38 / 0.35 (1.06 – 1.09). Leg Ⅰ: trochanter 0.08 – 0.10 / 0.09 (0.89 – 1.11), femur 0.31 – 0.33 / 0.05 – 0.06 (5.50 – 6.20), patella 0.16 / 0.05 (3.20), tibia 0.15 – 0.16 / 0.04 – 0.05 (3.00 – 4.00), tarsus 0.37 – 0.38 / 0.04 (9.25 – 9.50). Leg IV: trochanter 0.12 – 0.15 / 0.09 – 0.10 (1.20 – 1.67), femoropatella 0.42 – 0.44 / 0.17 – 0.18 (2.33 – 2.59), tibia 0.33 / 0.07 (4.71), metatarsus 0.16 / 0.05 (3.20), tarsus 0.37 – 0.38 / 0.04 (9.25 – 9.50). Females: body length 1.44 – 1.64. Pedipalps: trochanter 0.13 / 0.10 – 0.11 (1.18 – 1.30), femur 0.68 – 0.71 / 0.10 – 0.11 (6.45 – 6.80), patella 0.24 – 0.25 / 0.12 (2.00 – 2.08), chela 0.94 – 0.98 / 0.16 – 0.17 (5.76 – 5.88), hand 0.38 – 0.40 / 0.16 – 0.17 (2.35 – 2.38), movable chelal finger length 0.57 – 0.59. Chelicera 0.39 – 0.41 / 0.17 – 0.19 (2.16 – 2.29), movable finger length 0.20 – 0.22. Carapace 0.40 – 0.43 / 0.40 – 0.43 (1.00). Leg Ⅰ: trochanter 0.11 / 0.08 – 0.10 (1.10 – 1.38), femur 0.35 – 0.39 / 0.06 (5.83 – 6.50), patella 0.19 / 0.05 – 0.06 (3.17 – 3.80), tibia 0.17 – 0.18 / 0.04 – 0.05 (3.60 – 4.25), tarsus 0.40 – 0.43 / 0.04 (10.00 – 10.75). Leg IV: trochanter 0.13 – 0.15 / 0.11 – 0.12 (1.18 – 1.25), femoropatella 0.47 – 0.50 / 0.18 – 0.19 (2.47 – 2.78), tibia 0.35 / 0.07 – 0.08 (4.38 – 5.00), metatarsus 0.17 – 0.18 / 0.05 – 0.06 (3.00 – 3.40), tarsus 0.40 – 0.41 / 0.04 (10.00 – 10.25).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFB7FF95FF053847E3C23EAE.taxon	distribution	Distribution. Known only from the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFA8FF92FF053AC1E3C23A2E.taxon	description	Figs 40 – 43	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFA8FF92FF053AC1E3C23A2E.taxon	materials_examined	Type material. Holotype ♀ (Ps. - MHBU-GZC 190727 - 01 - 01): China, Guizhou Province, Suiyang County, Yangchuan Sub-district, Xinglong Village, Xiao Cave, under stones in the deep zone [27 ° 59 ′ 57.61 ″ N, 107 ° 10 ′ 31.85 ″ E], 976 m a. s. l., 27 July 2019, Zegang Feng, Zhaoyi Li & Chen Zhang leg. Paratype: 1 ♀ (Ps. - MSWU-GZC 190727 - 01 - 02), with the same data as the holotype.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFA8FF92FF053AC1E3C23A2E.taxon	etymology	Etymology. Named after the type locality, Xiao Cave.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFA8FF92FF053AC1E3C23A2E.taxon	diagnosis	Diagnosis (♀). Small-sized troglomorphic species with elongated appendages; carapace without eyes or eyespots; anterior margin of carapace thin, finely denticulated, epistome obtuse and small, round; posterior margin of carapace with two setae; tergites Ⅰ – VI each with four setae. Pedipalps slender, femur 5.91 – 6.09 times longer than broad; chela 6.33 – 6.47 times longer than broad; chelal fingers without intercalary teeth but fixed chelal finger with a modified accessory tooth (td) on retrolateral face; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFA8FF92FF053AC1E3C23A2E.taxon	description	Description. Females (holotype and paratype), male unknown (Figs 40 D, 41 – 43). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 42 C, 43 A): carapace 0.93 times longer than broad, gently narrowed posteriorly; surface smooth, without furrows; no traces of eyes; anterior margin slightly serrate; epistome obtuse and small, round, with two setae flanking base; with 18 setae arranged s 4 s: 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 setae of ocular row, second pair situated lateral to the sole pair of setae of posterior row. Chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 5; manducatory process with two acuminate distal setae, anterior seta more than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with 7 – 8 terminally indented coxal spines on each side, set as an oblique row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 43 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 42 D, 43 B): large, about as long as carapace, 2.15 times longer than broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 12 – 14 teeth, distal one largest; movable finger with 11 retrorse contiguous small teeth; galea represented by a very slight bump on movable finger (Fig. 43 B). Serrula exterior with 15 – 16 blades and serrula interior with 11 – 12 blades. Rallum with nine 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. 43 D). Pedipalp (Figs 42 A – B, F, 43 E – G): long and slender, trochanter 1.27, femur 5.91 – 6.09, patella 1.92 – 2.08, chela 6.33 – 6.47, hand 2.53 times longer than broad; femur 2.68 – 2.83 times longer than patella; movable chelal finger 1.50 – 1.58 times longer than hand and 0.60 – 0.62 times longer than chela. Setae generally long and acuminate; one distal lyrifissure present on patella (Figs 42 F, 43 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized, with weak granulation dorsally at base of fixed chelal finger and hand. 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 forming an oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb situated midway between st and b; b and t situated subdistally, t situated distal to b and between it and est; est distal to b (Fig. 43 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, homodentate, spaced regularly along the margin, larger and well-spaced teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 24 – 25 macrodenticles, slightly retrorse and pointed, plus a modified accessory tooth on retrolateral face (td, close to dx), 25 – 26 in total; movable chelal finger with ten macrodenticles (slightly smaller than teeth on fixed chelal finger), slightly retrorse and pointed, plus 14 – 16 vestigial, rounded and contiguous basal teeth, 24 – 26 in total (Fig. 43 F). Chelal fingers straight in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 42 B, 43 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 4: 4: 4: 4: 4: 4: 5: 5 – 6: 5 – 6: 4: T 2 T: 0. Sternal chaetotaxy IV – XII: 12 – 13: 10: 8 – 9: 8: 10 – 11: 10: 9 – 10: 0: 2. Anterior genital operculum with 10 – 11 setae, posterior margin with 13 – 16 marginal setae, 24 – 26 in total (Fig. 42 E). Legs (Fig. 43 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of femur IV and patella IV. Femur of leg Ⅰ 1.83 – 1.89 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.24 – 2.31 times longer than tibia. Femoropatella of leg IV 2.82 times longer than deep; tibia 4.25 – 4.86 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 2.83 – 3.00 times longer than deep (TS = 0.35 – 0.39), tarsus 9.50 times longer than deep and 2.11 – 2.24 times longer than metatarsus (TS = 0.32). Arolium slightly shorter than the claws, not divided; claws simple. Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Females: body length 1.25 – 1.47. Pedipalps: trochanter 0.14 / 0.11 (1.27), femur 0.65 – 0.67 / 0.11 (5.91 – 6.09), patella 0.23 – 0.25 / 0.12 (1.92 – 2.08), chela 0.95 – 0.97 / 0.15 (6.33 – 6.47), hand 0.38 / 0.15 (2.53), movable chelal finger length 0.57 – 0.60. Chelicera 0.43 / 0.20 (2.15), movable finger length 0.23. Carapace 0.40 / 0.43 (0.93). Leg Ⅰ: trochanter 0.11 – 0.12 / 0.10 (1.10 – 1.20), femur 0.33 – 0.34 / 0.06 (5.50 – 5.67), patella 0.18 / 0.05 – 0.06 (3.00 – 3.60), tibia 0.16 – 0.17 / 0.04 (4.00 – 4.25), tarsus 0.37 – 0.38 / 0.04 (9.25 – 9.50). Leg IV: trochanter 0.16 – 0.17 / 0.11 (1.45 – 1.55), femoropatella 0.48 / 0.17 (2.82), tibia 0.34 / 0.07 – 0.08 (4.25 – 4.86), metatarsus 0.17 – 0.18 / 0.06 (2.83 – 3.00), tarsus 0.38 / 0.04 (9.50).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFA8FF92FF053AC1E3C23A2E.taxon	distribution	Distribution. Known only from the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFACFF98FF053900E4AF3C46.taxon	description	Figs 44 – 47	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFACFF98FF053900E4AF3C46.taxon	materials_examined	Type material. Holotype ♀ (Ps. - MHBU-GZZJ- 19 - 04 - 01): China, Guizhou Province, Zhijin County, Chengguan Town, Yangliu Village, Long Cave, under stones in the deep zone [26 ° 40 ′ 45.63 ″ N, 105 ° 47 ′ 16.30 ″ E], 1345 m a. s. l., 2 October 2019, Zegang Feng & Lingchen Zhao leg. Paratype: 1 ♀ (Ps. - MSWU-GZZJ- 19 - 04 - 02), with the same data as the holotype.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFACFF98FF053900E4AF3C46.taxon	etymology	Etymology. Named after the Zhijin County, near the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFACFF98FF053900E4AF3C46.taxon	diagnosis	Diagnosis (♀). Moderately sized troglomorphic species with elongated appendages; carapace without eyes or eyespots; anterior margin of carapace thin, finely denticulated, epistome pointed and small, triangular; posterior margin of carapace with two setae; tergites II – III each with two setae, tergites IV – VII each with four setae. Pedipalps slender, femur 8.47 – 8.53 times longer than broad; chela 7.46 – 7.71 times longer than broad; only fixed chelal finger with intercalary teeth and a modified accessory tooth (td) on retrolateral face; chelal fingers slightly curved in dorsal view; chemosensory setae (sc) present on dorsum of chelal hand.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFACFF98FF053900E4AF3C46.taxon	description	Description. Females (holotype and paratype), male unknown (Figs 45 – 47). Colour: generally pale yellow, chelicerae, pedipalps and tergites slightly darker, soft parts pale. Cephalothorax (Figs 46 C, 47 A): carapace 0.93 – 0.98 times longer than broad, gently narrowed posteriorly; surface smooth, without furrows; no traces of eyes; anterior margin slightly serrate; epistome pointed and small, triangular; with 18 setae arranged s 4 s: 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. Chaetotaxy of coxae: P 3, Ⅰ 3, II 4, III 5, IV 5 – 6; manducatory process with two acuminate distal setae, anterior seta less than 1 / 2 length of medial seta; apex of coxa Ⅰ with small, rounded anteromedial process; coxae II with 11 – 12 terminally indented coxal spines on each side, set as an oblique and arc row, longer spines present in the middle of the row, becoming shorter distally and proximally and incised for about half their length (Fig. 47 C); intercoxal tubercle absent; without sub-oral seta. Chelicera (Figs 46 D, 47 B): large, about as long as carapace, 2.29 – 2.31 times longer than broad; five setae and two lyrifissures (exterior condylar lyrifissure and exterior lyrifissure) present on hand, all setae acuminate, ventrobasal seta shorter than others; movable finger with one medial seta. Cheliceral palm with moderate hispid granulation on both ventral and dorsal sides. Both fingers well provided with teeth, fixed finger with 20 – 24 teeth, distal one largest; movable finger with 18 – 19 retrorse contiguous small teeth; galea absent (Fig. 47 B). Serrula exterior with 20 – 21 blades and serrula interior with 13 – 15 blades. Rallum with seven 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. 47 D). Pedipalp (Figs 46 A – B, F, 47 E – G): long and slender, trochanter 1.25 – 1.32, femur 8.47 – 8.53, patella 2.21 – 2.37, chela 7.46 – 7.71, hand 3.04 – 3.17 times longer than broad; femur 2.84 – 3.02 times longer than patella; movable chelal finger 1.42 – 1.45 times longer than hand and 0.58 – 0.59 times longer than chela. Setae generally long and acuminate; one distal lyrifissure present on patella (Figs 46 F, 47 E). Chelal palm gradually constricted towards fingers, apodeme complex of movable chelal finger strongly sclerotized, with weak granulation dorsally at base of fixed chelal finger. 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 forming a straight oblique row at base of fixed chelal finger; it slightly distal to est, situated subdistally; et slightly near to tip of fixed chelal finger, very close to chelal teeth; dx situated distal to et; sb situated midway between b and st; b and t situated subdistally and situated at the same level as est and it, respectively (Fig. 47 F). A tiny retrolateral lyrifissure present at base of fixed chelal finger (situated distal to ist). Both chelal fingers with a row of teeth, heterodentate, spaced regularly along the margin, larger teeth present in the middle of the row, becoming smaller and closer distally and proximally: fixed chelal finger with 23 macrodenticles, slightly retrorse and pointed, plus 11 – 12 intercalary microdenticles, 34 – 35 in total; movable chelal finger with 21 – 22 macrodenticles (slightly smaller than teeth on fixed chelal finger), slightly retrorse and pointed, plus 7 – 8 vestigial, rounded and contiguous basal teeth, 28 – 30 in total (Fig. 47 F). Chelal fingers slightly curved in dorsal view; microsetae (chemosensory setae) present on dorsum of chelal hand (Figs 46 B, 47 G). Opisthosoma: generally typical, pleural membrane finely granulated. Tergites and sternites undivided; setae uniseriate and acuminate. Tergal chaetotaxy Ⅰ – XII: 2 – 3: 2: 2: 4: 4: 4: 4: 5: 5: 2: T 2 T: 0, tergites VIII and IX each with an unpaired median seta. Sternal chaetotaxy IV – XII: 13: 9: 9 – 10: 8 – 9: 9: 9: 7 – 8: 0: 2. Anterior genital operculum with 9 – 10 setae, posterior margin with 12 – 14 marginal setae, 21 – 24 in total (Fig. 46 E). Legs (Fig. 47 H – I): generally typical, long and slender. Fine granulation present on anterodorsal faces of femur IV and patella IV. Femur of leg Ⅰ 1.76 – 1.79 times longer than patella and with one lyrifissure at the base of femur; tarsus 2.48 – 2.56 times longer than tibia. Femoropatella of leg IV 4.12 – 4.13 times longer than deep; tibia 6.27 – 6.36 times longer than deep; with basal tactile setae on both tarsal segments: metatarsus 3.56 times longer than deep (TS = 0.28 – 0.34), tarsus 14.17 – 14.33 times longer than deep and 2.66 – 2.69 times longer than metatarsus (TS = 0.31 – 0.34). Arolium slightly shorter than the claws, not divided; claws simple. Dimensions (length / breadth or, in the case of the legs, length / depth in mm; ratios in parentheses). Females: body length 2.17 – 2.36. Pedipalps: trochanter 0.25 / 0.19 – 0.20 (1.25 – 1.32), femur 1.27 – 1.28 / 0.15 (8.47 – 8.53), patella 0.42 – 0.45 / 0.19 (2.21 – 2.37), chela 1.79 – 1.85 / 0.24 (7.46 – 7.71), hand 0.73 – 0.76 / 0.24 (3.04 – 3.17), movable chelal finger length 1.06 – 1.08. Chelicera 0.71 – 0.74 / 0.31 – 0.32 (2.29 – 2.31), movable finger length 0.37 – 0.38. Carapace 0.62 – 0.65 / 0.66 – 0.67 (0.93 – 0.98). Leg Ⅰ: trochanter 0.19 – 0.21 / 0.16 (1.19 – 1.31), femur 0.70 – 0.72 / 0.09 (7.78 – 8.00), patella 0.39 – 0.41 / 0.08 – 0.09 (4.56 – 4.88), tibia 0.31 – 0.32 / 0.06 (5.17 – 5.33), tarsus 0.77 – 0.82 / 0.06 – 0.07 (11.71 – 12.83). Leg IV: trochanter 0.28 – 0.29 / 0.16 – 0.18 (1.61 – 1.75), femoropatella 0.99 – 1.03 / 0.24 – 0.25 (4.12 – 4.13), tibia 0.69 – 0.70 / 0.11 (6.27 – 6.36), metatarsus 0.32 / 0.09 (3.56), tarsus 0.85 – 0.86 / 0.06 (14.17 – 14.33).	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
03DA1A1EFFACFF98FF053900E4AF3C46.taxon	distribution	Distribution. Known only from the type locality.	en	Hou, Yanmeng, Feng, Zegang, Zhang, Feng (2023): New cave-dwelling pseudoscorpions of the genus Lagynochthonius (Pseudoscorpiones, Chthoniidae) from Guizhou in China. Zootaxa 5309 (1): 1-64, DOI: 10.11646/zootaxa.5309.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5309.1.1
