Gonatium tridentatum, Irfan & Zhang & Cai & Zhang, 2025

Irfan, Muhammad, Zhang, Chang-Cheng, Cai, Yu-Jun & Zhang, Zhi-Sheng, 2025, Four new species of Linyphiidae spiders (Arachnida: Araneae) from Jiangjin District of Chongqing, China, Zootaxa 5647 (5), pp. 435-450 : 436-440

Gonatium tridentatum sp. nov. (三ŝiñe)

Figures 3–5, 13

Type material. CHINA: Chongqing Mun, Jiangjin Dist., Simian Mt. Nature Reserve: Holotype ♂ (SWUC-T- LIN-34-01), Zhenzhutan , 28°35′50.74″N, 106°25′25.70″E, 1226 m a.s.l., 06.II.2023, C.Y Huang. and D.H. Chen leg. Paratypes: 2♀ (SWUC-T-LIN-34-02~03), with same data as holotype; 1♀ (SWUC-T-LIN-34-04), Tudiyan , 28°37′24.45″N, 106°24′6.69″E, 1126 m a.s.l., 02.III.2023 , Z.G. Zhang et al. leg.; 1♀ (SWUC-T-LIN-34-05), Qinjiagou , 28°37′6.32″N, 106°23′53.40″E, 1131 m a.s.l., 30.III.2023 , Z.G. Zhang et al. leg.; 1♀ (SWUC-T-LIN-34-06), Dawopu , 28°34.774′N, 106°21.563′E, 1092 m a.s.l., 11.XI.2011, L.Y. Wang and Z.X. Li leg. ; 1♀ (SWUC- T-LIN-34-07), around Dahonghai Lake , 28°35′34.27″N, 106°26′34.93″E, 1144 m a.s.l., 10.I.2023, L.Y. Cheng and C.Y. Lin leg. ; 1♀ (SWUC-T-LIN-34-08), around Dahonghai Lake , 28°36.148′N, 106°26.871′E, 1193 m a.s.l., 17.VII.2011, L.Y.Wang and M.X. Liu leg.

Etymology. The specific epithet is derived from the Latin adjective " tri and dentatus " meaning "three and teeth" referring to the retrolateral basal process of tibial apophysis (BPA) proximally with three teeth in dorsal view in male palp.

Diagnosis. Gonatium tridentatum sp. nov. belongs to japonicum -group and resembles G. japonicum Simon, 1906 in having the similar unmodified femur, long dorsal tibial apophysis (TBA) extending above the apex of cymbium and the copulatory opening (CO) located anteriorly, with long internal copulatory (CD) ( Figs 3A–D, 4A–D; Zhang et al. 2022 figs 36A–G), and can be distinguished by retrolateral basal process of tibial apophysis (BPA) with 3 teeth ( Figs 3C; vs. one tooth); ectal part of spermathecae globular ( Fig. 4C; vs. elliptical).

Description. Male (holotype, Fig. 5A–C). Total length 2.27; carapace 1.05 long, 0.93 wide, yellow, cephalic region elevated, ocular area black, clypeus and ocular area with microsetae, cervical and radial grooves distinct. Clypeus 0.25 high. Chelicerae with 4 promarginal and 3 retromarginal teeth. Sternum triangular-shaped, as wide as long yellow. Eyes: AER recurved, PER straight, slightly wider than AER. Eye sizes and interdistances: AME 0.05, ALE 0.09, PME 0.09, PLE 0.08, AME–AME 0.02, PME–PME 0.07, AME–ALE, 0.06, PME–PLE 0.05, AME– PME 0.05, ALE–ALE 0.37, PLE–PLE 0.39, ALE–PLE contiguous. Legs I–IV ventrally with row of thick spines. Length of legs: I 3.76 (1.12, 0.37, 1.06, 0.76, 0.45), II 3.61 (1.06, 0.34, 0.99, 0.79, 0.43), III 3.06 (0.86, 0.30, 0.70, 0.79, 0.41), IV 3.70 (1.03, 0.33, 0.92, 0.96, 0.46). TmI 0.89 and TmIV 0.84. Opisthosoma 1.29 long, 0.95 wide, oval, gray, dorsally with 2 pairs of sigillae, ventral side dusky gray.

Palp ( Fig. 3A–D). Femur cylindrical, slightly longer than patella and tibia; patella 3 times longer than basal part of tibia, slightly curved mesally. Tibia with one retrolateral trichobothrium, dorsally with C-shaped tibial apophysis (TBA), closely applied to dorsal side of cymbium, long, extending above retrolateral margin of cymbium; retrolateral basal process of tibial apophysis (BPA) heavily sclerotized, strongly curved ventrally grooved, with 3 teeth; cymbium hoof-shaped, retrolateral margin with small outgrowth visible in dorsal view; paracymbium (PC) simple, hook-shaped; tegulum (T) round with long membranous L-shaped protegulum (PT); distal suprategular apophysis (DSA) membranous. Tailpiece (TP) spindle-shaped, slightly curved, with blunt tip; embolus (E) long, curved, accompanied by embolic membrane (EM) extending above cymbium apex.

Female (paratype, SWUC-T-LIN-30-02, Fig. 5D, E). Total length 2.92; carapace 1.08 long, 0.94 wide, yellow, cephalic region slightly elevated, ocular region black, fovea, cervical and radial grooves distinct. Clypeus 0.22 high. Chelicerae with four promarginal and four retromarginal teeth. Sternum yellow, as long as wide. Eyes: AER recurved, PER straight, slightly wider than AER. Eye sizes and interdistances: AME 0.05 ALE 0.10, PME 0.08, PLE 0.08, AME–AME 0.02, PME–PME 0.06, AME–ALE, 0.06, PME–PLE 0.05, AME–PME 0.06, ALE–ALE 0.40, PLE–PLE 0.42, ALE–PLE 0.01. Length of legs: I 4.00 (1.14, 0.36, 1.08 0.94, 0.48), II 3.93 (1.12, 0.35, 1.06, 0.93, 0.47), III 3.27 (0.92, 0.29,0.81, 0.82, 0.43), IV 4 (1.14, 0.31, 1.03, 1.03, 0.51). TmI 0.87 and TmIV 0.88. Opisthosoma 1.52 long, 0.96 wide, oval, pale, dorsally with gray band.

Epigyne ( Fig. 4A–D). Epigynal plate wider than long; copulatory opening (CO) located anteriorly; dorsal plate (DP) somewhat rectangular, posterior margin with depression; copulatory ducts (CD) long, spirally coiled anteriorly; spermathecae (S) with mesal and ectal part, present laterally on dorsal plate, pointing away from each other; fertilization ducts (FD) short, extending mesally.

Distribution. Known only from the type localities in Jiangjin District, Chongqing ( Fig. 13).