Walckenaeria extenuata Irfan, Zhang & Peng, sp. n.
Creators: name: Irfan, Muhammad
name: Zhou, Gu-Chun
name: Peng, Xian-Jin
name: Zhang, Zhi-Sheng
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Linyphiidae
Walckenaeria
Walckenaeria extenuata

description: Walckenaeria extenuata Irfan, Zhang & Peng, sp. n.
(ādĩe)
Figures 274–277, 314, 315
Types. Holotype ♂ (HNU–HNDWS–18–05), CHINA, Hunan Prov.: Liuyang City, Mudu Vill., Daweishan NFP, 28.43388°N, 114.03376°E, 379 m, 14.I.2018, G.C. Zhou et al. leg. Paratypes: 1♂ 15♀, with same data as for holotype male (HNU–HNDWS–18–05); 1♀, Zhangjiajie City, Wulingyuan District, Suoxiyu Town, Tujia Township, Wenfeng Vill., 29.35692°N, 110.54491°E, 476 m, 18.IV.2018, D. Li et al. leg. (HNU–HN– IV–1804); 6♀, Hubei Prov.: Xuanen Co., Shadaogou Town, Qizimei Mountain, 29.706342°N, 109.75642°E, 1155 m, 30.IV.2016, W. Liu et al. leg. (HNU–HB 2016–04–30).
Etymology. The specific epithet is derived from the Latin adjective “extenuatus” meaning “fine” and referring to the very fine and thin end of embolus in male palp.
Diagnosis. Walckenaeria extenuata sp. n. can be distinguished from all congeners by the tibia with three apophyses, dorsal tibial apophysis tip with several small teeth and ventrally with larg tooth; prolateral and ventral tibial apophyses thumb-shaped; distal suprategular apophysis tip ear lobe-shaped protruding upward in male palp(Figs274A–D, 275A–C).Female can be distinguished by the dorsal plate with one pair of protrusions posteriorly with copulatory openings in epigyne; spermathecae oval, encircled by the broad loops of copulatory ducts (Figs 276A–D).
Description. Male (holotype, Figs 277A–C): Total length: 1.55. Carapace 0.71 long, 0.57 wide, brown, with two small, round cephalic lobes behind the PMEs and at the base of PLEs with cephalic pits on each side; fovea, cervical and radial grooves distinct. Clypeus 0.27 high. Chelicerae with three promarginal and five retromarginal teeth. Sternum shield-like, brownish grey with microsetae. Eyes: AER recurved, PER procurved, slightly wider than AER. Eye sizes and interdistances: AME 0.04, ALE 0.06, PME 0.05, PLE 0.05, AME–AME 0.02, PME–PME 0.04, AME–ALE, 0.04, PME–PLE 0.05, AME–PME 0.04, ALE–ALE 0.25, PLE–PLE 0.27, ALE–PLE contiguous. Length of legs: I 2.26 (0.65, 0.79, 0.54, 0.28), II 2.14 (0.62, 0.71, 0.49, 0.32), III 1.69 (0.47, 0.54, 0.43, 0.25), IV 2.17 (0.63, 0.68, 0.55, 0.31). Tibial spine formula: 2-2- 1-1. TmI and TmIV present. Opisthosoma 0.89 long, 0.60 wide, oval, grey, with two pairs of sigillae.
Palp (Figs 274A–D, 275A–C): Femur unmodified, almost longer than both patella and tibia. Patella shorter than tibia, ventrally grooved. Tibia with two retrolateral and one dorsal trichobothria and three apophyses; ventral tibial apophysis (VTA) and prolateral tibial apophysis (PTA) thumb-shaped with blunt end; dorsal tibial apophysis (DTA) rectangular longer than wide, curved, tip ventrally with large tooth and tip with several teeth; cymbium unmodified, broad at distal end; paracymbium (PC) C-shaped, distal arm tip knobbed; distal suprategular apophysis (DSA) tip ear lobe-shaped protruding upward. Embolic division: Radix (R) spirally coiled protruding upward; tailpiece (TP) sclerotized, strongly curved with blunt tip, pointing towards the tibia; embolic membrane (EM)running parallel with embolus and distal suprategular apophysis; embolus (E) sclerotized, forming a complete circle, distal part very fine and thin.
Female (one of paratype, Figs 277D, E): Total length: 1.77. Carapace 0.72 long, 0.56 wide, dark brown, fovea, cervical and radial grooves distinct. Clypeus 0.18 high. Chelicerae with five promarginal and six retromarginal teeth. Sternum shield-like, brownish grey with microsetae. Eyes: AER recurved, PER straight, slightly wider than AER. Eye sizes and interdistances: AME 0.05, ALE 0.05, PME 0.05, PLE 0.05, AME–AME 0.01, PME–PME 0.04, AME–ALE, 0.03, PME–PLE 0.05, AME–PME 0.04, ALE–ALE 0.24, PLE–PLE 0.27, ALE–PLE 0.01. Length of legs: I 2.11 (0.62, 0.71, 0.51, 0.27), II 2.06 (0.63, 0.70, 0.48, 0.25), III 1.76 (0.57, 0.52, 0.39, 0.25), IV 2.16 (0.69, 0.67, 0.52, 0.28). Tibial spine formula: 2-2-1-1. TmI and TmIV present. Opisthosoma 1.17 long, 0.85 wide, oval, grey, with two pairs of sigillae.
Epigyne (Figs 276A–D): Ventral plate (VP) wider than long; dorsal plate (DP) somewhat round, with pair of tubercles posteriorly with copulatory openings (CO). Spermathecae (S) oval, encircled by the broad loops of copulatory ducts (CD); fertilization ducts (FD) small, extending mesally.
Distribution. Known only from the type localities (Hubei and Hunan Provinces, Figs. 314, 315).
description: Published as part of Irfan, Muhammad, Zhou, Gu-Chun, Peng, Xian-Jin & Zhang, Zhi-Sheng, 2025, Survey of Linyphiidae spiders (Arachnida: Araneae) from some Oriental Regions of China, pp. 1-248 in Megataxa 15 (1) on pages 207-210, DOI: 10.11646/megataxa.15.1.1, http://zenodo.org/record/14985176