Lechytia acutidentata, Sun & Guo & Zhang, 2024

Sun, Jianzhou, Guo, Xiangbo & Zhang, Feng, 2024, Revision of the genus Lechytia Balzan, 1892 (Pseudoscorpiones, Chthoniidae) from China, with descriptions of two new species, Biodiversity Data Journal 12, pp. 122612-122612 : 122612

Lechytia acutidentata sp. nov.

Materials

Type status: Holotype. Occurrence: recordedBy: Xiangbo Guo, Bo Liu & Haibin Zhang; sex: female; lifeStage: adult; occurrenceID: 3E280ECF-CA68-54EE-A007-D55C009D6828; Taxon: scientificName: Lechytia acutidentata; Location: country: China; stateProvince: Xizang Autonomous Region; county: Jilong; locality: Jilong Town, Rema Village , under bark ; verbatimElevation: 3272 m; verbatimCoordinates: 28.455680°N, 85.196614°E; Identification: identifiedBy: Jianzhou Sun; Event: eventID: HBUARA#2023-880; year: 2023; month: August; day: 2; Record Level: institutionID: the Museum of Hebei University (MHBU); institutionCode: Ps.-MHBU-XZ 2023080201 Type status: Paratype. Occurrence: recordedBy: Xiangbo Guo, Bo Liu & Haibin Zhang; sex: 1 male, 31 females; lifeStage: adult; occurrenceID: 2053BC16-16DC-5FC4-A9C5-76DA95B44FEC; Taxon: scientificName: Lechytia acutidentata; Location: country: China; stateProvince: Xizang Autonomous Region; county: Jilong; locality: Jilong Town, Rema Village , under bark ; verbatimElevation: 3272 m; verbatimCoordinates: 28.455680°N, 85.196614°E; Identification: identifiedBy: Jianzhou Sun; Event: eventID: HBUARA#2023-880; year: 2023; month: August; day: 2; Record Level: institutionID: the Museum of Hebei University; institutionCode: male (Ps.-MHBU-XZ2023080202) and 31 females (Ps.-MHBU-XZ2023080203-033)

Description

Females (holotype and paratypes) (Fig. 1 B, Fig. 2 A-H, K and Figs 3 , 4 A-D).

Cephalothorax (Fig. 2 D, E and Fig. 3 A): carapace nearly subquadrate, 0.98-1.09 times longer than broad; anterior margin denticulate; without epistome; two small corneate eyes; with 18 setae arranged 6: 4: 4: 2: 2, most setae heavy, long and gently curved; with four pairs of lyrifissures, first pair situated antero-medially, the second pair situated interno-underneath to the eyes, the third pair situated slightly interior to the sole pair of setae of the intermediate row and the fourth pair situated exterior to the sole pair of setae of the posterior row. Manducatory process with two acuminate distal setae, about equal in length, the distal setae terminally acuminate (Fig. 5 C); apex of coxa I with a triangular apical projection (Fig. 5 D); coxal spines and intercoxal tubercle absent. Chaetotaxy of coxae: P 5, Ⅰ 7, II 7, III 7, IV 7.

Chelicera (Fig. 2 C and Fig. 3 B): 1.39-1.56 times longer than broad; five setae present on hand, all setae acuminate, ventrobasal setae shorter than others; movable finger with one medial seta. Cheliceral palm has moderate wrinkles on both ventral and dorsal sides. Fixed finger with one large tooth and two roughened ridges proximally; movable finger with an acute apical tooth and four pointed, conspicuous middle teeth; galea shaped like a tooth (♂♀) (Fig. 2 C, I, Fig. 3 B and Fig. 4 F). Serrula exterior with 17-18 blades, smooth surface and side creases (Fig. 5 B). Rallum with eight blades, subdistal blade strongly recumbent, others in straight row (Fig. 3 D and Fig. 5 A).

Pedipalp (Fig. 2 A, B, H, Fig. 3 E, Fig. 4 A and B): trochanter 1.54-1.91, femur 3.86-4.73, patella 1.76-1.88, chela 3.59-3.90, hand 1.54-1.75 times longer than broad; femur 1.73-1.80 times longer than patella; movable chelal finger 1.28-1.42 times longer than hand and 0.57-0.61 times longer than chela. Setae generally long and acuminate. Fixed chelal finger and hand with eight trichobothria, ib, isb, eb and esb on dorsum of hand, ib and isb basally, esb submedially, eb closer to ib and isb than to esb; ist situated basally on fixed finger, est and it situated submedially and medially on fixed finger, et and dx distally; movable chelal finger with four trichobothria, b closer to sb than to t, sb closer b than to st; b and sb situated more than one diameter apart (Fig. 2 A, Fig. 4 A, Fig. 5 E and F); sensilla absent. Both chelal fingers with a row of teeth: fixed finger with 50-52 developed retrorse, pointed teeth; movable finger with 48-53 upright, pointed teeth.

Opisthosoma: tergites and sternites undivided; setae acuminate. Tergal chaetotaxy I-Ⅻ: 6: 4-6: 5-6: 6-7: 6: 6: 6: 6: 6: 4-6: T2T: 0. Sternal chaetotaxy Ⅳ-Ⅻ: 14-16: 12: 10: 10-12: 8-10: 8: 5-6: -: 2. Genital area weakly sclerotised with U-shaped frame (Fig. 2 K).

Legs (Fig. 2 F, G, Fig. 4 C and D): leg Ⅰ: femur 1.56-1.93 times longer than patella; tarsus 1.61-1.76 times longer than tibia. Leg Ⅳ: femoropatella 2.10-2.50 times longer than deep; tibia 3.78-4.25 times longer than deep; with sub-basal tactile setae on basitarsal segments. Arolium slightly shorter than the claws, not divided; claws simple.

Adult male (paratype) (Fig. 1 A, Fig. 2 J, Fig. 3 C, Fig. 4 E and F). Mostly same as females, but a little smaller on average; tergal chaetotaxy Ⅰ-Ⅻ: 6: 6: 6: 6: 6: 6: 6: 6: 6: 4: T2T: 0; sternal chaetotaxy Ⅳ-Ⅻ: 14: 10: 8: 8: 8: 8: 6: -: 2. Genital region: partial setaes bifurcate.

Dimensions (length/breadth or, in the case of the legs, length/depth in mm; ratios in parentheses). Male: body length 1.71. Pedipalps: trochanter 0.21/0.11 (1.91), femur 0.49/0.12 (4.08), patella 0.29/0.17 (1.71), chela 0.75/0.19 (3.95), hand 0.32/0.19 (1.68), movable chelal finger length 0.44. Chelicera 0.24/0.16 (1.50), movable finger length 0.12. Carapace 0.45/0.39 (1.15). Leg I: trochanter 0.18/0.11 (1.64), femur 0.29/0.06 (4.83), patella 0.13/0.05 (2.60), tibia 0.12/0.05 (2.40), tarsus 0.25/0.04 (6.25). Leg Ⅳ: trochanter 0.16/0.09 (1.78), femoropatella 0.37/0.18 (2.06), tibia 0.33/0.09 (3.67), basitarsus 0.16/0.06 (2.67), telotarsus 0.22/0.04 (5.50).

Females: body length 1.79-2.07. Pedipalps: trochanter 0.20-0.21/0.11-0.13 (1.54-1.91), femur 0.51-0.54/0.11-0.14 (3.86-4.73), patella 0.29-0.30/0.16-0.17(1.76-1.88), chela 0.77-0.82/0.20-0.22 (3.59-3.90), hand 0.32-0.37/0.20-0.22 (1.54-1.75), movable chelal finger length 0.45-0.48. Chelicera 0.25-0.29/0.18-0.20 (1.39-1.56), movable finger length 0.15-0.16. Carapace 0.43-0.47/0.42-0.46 (0.98-1.09). Leg I: trochanter 0.11-0.14/0.08-0.11 (1.18-1.75), femur 0.25-0.29/0.06-0.07 (3.71-4.83), patella 0.15-0.16/0.05-0.07 (2.14-3.00), tibia 0.12-0.17/0.05 (3.20-3.60), tarsus 0.27-0.30/0.04-0.05 (5.60-7.50). Leg Ⅳ: trochanter 0.15-0.19/0.09-0.14 (1.25-1.78), femoropatella 0.42-0.45/0.18-0.20 (2.10-2.50), tibia 0.33-0.35/0.08-0.09 (3.78-4.25), basitarsus 0.16-0.18/0.06-0.07 (2.29-2.83), telotarsus 0.23-0.24/0.04-0.05 (4.60-6.00).

Diagnosis

The new species belongs to the Lechytia hoffi species-group and is characterised by the following combination of characteristics: trichobothria b and sb situated more than one areolar diameter apart; movable chelal finger with upright and point teeth; palpal chela 3.59-3.90 (♀), 3.95 (♂) and palpal hand 1.54-1.75 (♀), 1.68 (♂) longer than broad; palpal femur 0.51-0.54 mm (♀), 0.49 mm (♂), palpal hand 0.33-0.37 mm (♀), 0.32 mm (♂) and chelal movable finger 0.45-0.48 mm (♀), 0.44 mm (♂) long.

Lechytia acutidentata sp. nov. most resembles L. yulongensis due to trichobothria b and sb on movable chelal finger situated more than one areolar diameter apart. However, the new species differs from L. yulongensis in the pattern of teeth of fixed chelal finger with upright and point teeth in L. acutidentata sp. nov., but retrorse and point teeth in L. yulongensis ( Zhang and Zhang 2014).

Etymology

The specific name is derived from a combination of the Latin words " acutus " and " dentatus ", meaning pointed and toothed, respectively, which refers to the pointed teeth on the movable chelal fingers.

Distribution

China (Xizang Autonomous Region).

Ecology

All specimens were collected under bark in denser forests (Fig. 6 ).

Biology

Their rounded nests are built by thin silks and had a thicker centre (Fig. 6 A and C). Some silk nests are close together, but independent from each other (Fig. 6 A).

Notes

Generally, the holotypes of Lechytia species are male specimens. Here, we chose a female specimen as the holotype of L. acutidentata , because the sole male specimen has a rather transparent and brittle body. It was probably caught and soaked in alcohol straight after just moulting.

Figures

Figure 1. Lechytia acutidentata sp. nov. A Paratype male (dorsal view); B Holotype female (dorsal view). Scale bars: 0.50 mm.

Figure 2. Lechytia acutidentata sp. nov., holotype female (A-H, K), paratype male (I, J): A Female left chela (lateral view); B Left chela (dorsal view); C Left chelicera (dorsal view); D Coxal area and manducatory process (ventral view); E Carapace (dorsal view); F Leg Ⅳ (lateral view); G Leg Ⅰ (lateral view); H Left pedipalp (minus chela, dorsal view); I Male left chelicera (dorsal view); J Male genital area (ventral view); K Female genital area (ventral view). Scale bars: 0.20 mm (A, B, D, H); 0.10 mm (C, E-G, I-K).

Figure 3. Lechytia acutidentata sp. nov., holotype female: A Carapace (dorsal view); B Left chelicera (dorsal view), with details of teeth; C Chaetotaxy of genital area (sternites II-III) (male); D Rallum; E Left pedipalp (minus chela, dorsal view). Scale bars: 0.10 mm (A-C); 0.05 mm (D); 0.20 mm (E).

Figure 4. Lechytia acutidentata sp. nov., holotype female (A-D), paratype male (E, F): A Left chela (lateral view), with details of teeth and trichobothrial pattern; B Left chela (dorsal view); C Leg I (lateral view); D Leg IV (lateral view); E Left chela (lateral view), with details of teeth and trichobothrial pattern; F Left chelicera (dorsal view), with details of teeth. Scale bars: 0.20 mm (A, B, E); 0.10 mm (C, D, F).

Figure 5. Lechytia acutidentata sp. nov., paratype female: A Rallum; B Serrula exterior; C Manducatory process (ventral view); D Coxal area (ventral view); E Right chela (lateral view), with details of teeth and trichobothrial pattern; F Chelal basal details of teeth and trichobothrial.

Figure 6. Type locality of Lechytia acutidentata sp. nov. A Numerous L. acutidentata sp. nov. and silk nests; B A living of L. acutidentata sp. nov. in its natural environment; C Silk nests of L. acutidentata sp. nov.; D-F. The habitat where L. acutidentata sp. nov. specimens were collected.