Sinisterigone incurvatis, Irfan & Zhang & Peng, 2022

Irfan, Muhammad, Zhang, Zhi-Sheng & Peng, Xian-Jin, 2022, Survey of Linyphiidae (Arachnida: Araneae) spiders from Yunnan, China, Megataxa 8 (1), pp. 1-292 : 259-263

Sinisterigone incurvatis sp. nov. (ỆǺẮƦ)

Figures 295 , 297

Types. Holotype ♀, CHINA, Yunnan, Houqiao Township, Gaoshidong , 25.39859°N, 98.30531°E, alt. 2374m, 27 May 2006, Xin-ping Wang and Peng Hu leg. (Wang060527–2).

Etymology. This epithet derives from the Latin adjective “ incurvatus ”, meaning “bent”, referring to the copulatory ducts bent inward in epigyne.

Diagnosis. This new species can be distinguished from all other the congeners by the copulatory ducts with a single spiral curved inward, pointing towards each other ( Fig. 295B, C ).

Description. Female (holotype, Fig. 295A ): Total length: 2.27. Carapace 0.92 long, 0.73 wide; cephalic region slightly elevated, brown; fovea, cervical and radial grooves distinct. Clypeus 0.22 high. Sternum wider than long, brown,, sparsely covered with microsetae. Labium wider than long. Maxillae long, distal end broad with scopulae. Chelicerae sclerotized, brown, with four promarginal and five retromarginal teeth. Eyes: AER recurved, PER straight, slightly wider than AER. Eye sizes and interdistances: AME 0.05, ALE 0.05, PME 0.04, PLE 0.06, AME–AME 0.03, PME–PME 0.06, AME–ALE, 0.02, PME–PLE 0.05, AME–PME 0.05, ALE–ALE 0.27, PLE–PLE 0.31, ALE–PLE contiguous. Length of legs: I 3.98 (1.11, 1.25, 1.01, 0.51), II 3.80 (1.10, 1.19, 0.94, 0.57), III 2.73 (0.81, 0.83, 0.65, 0.44), IV 3.51 (1.08, 1.05, 0.93, 0.45). Leg formula I-II-IV-III. Tm I and Tm IV present. Tibial spine formula: 2-2-1-1. Abdomen 1.35 long, 0.94 wide, oval, pale, mid dorsally with a longitudinal pale band followed by five transverse dark chevrons, ventral side pale.

Epigyne ( Fig. 295B, C ): Ventral plate wider than long; copulatory openings present at the junction of ventral and dorsal plate. Vulva: Dorsal plate round, broad, slightly depressed inward; copulatory ducts long, sclerotized, with a single spiral curved inward, pointing towards each others; spermathecae globular, fused with copulatory ducts, pointing away from each other; fertilization ducts thick, extending mesally.

Male. Unknown.

Distribution. Known only from the type locality ( Fig. 297 ).

Figures

FIGURE 295. Sinisterigone incurvatis sp. nov., female holotype. A Habitus, dorsal view B Epigyne, ventral view C Vulva, dorsal view.

FIGURE 297. Distribution of Sinisterigone gen. nov.