Sinisterigone rutundis, 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 : 263

Sinisterigone rutundis sp. nov. (ṆǺẮƦ)

Figures 296 , 297

Types. Holotype ♀, CHINA, Yunnan, Tengchong County, Shangyin Township, Cuanlong Village , 25.00667°N, 98.70992°E, alt. 1990m, 4 June 2006, Chang-min Yin,

Jia-fang Hu, Ming-wei Yang and Shao-xian He leg. (YHY25).

Etymology. This epithet derives from the Latin adjective “ rutundus ”, meaning “globular”, referring to the globular spermathecae in epigyne.

Diagnosis. This new species can be distinguished from all other congeners by the copulatory ducts with two coiled spirals ( Fig. 296B, C ).

Description. Female (holotype, Fig. 297A ): Total length: 2.50. Carapace 0.97 long, 0.79 wide; cephalic region slightly elevated, brown; fovea, cervical and radial grooves distinct. Clypeus 0.29 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 five promarginal and five retromarginal teeth. Eyes: AER recurved, PER straight, slightly wider than AER. Eye sizes and interdistances: AME 0.06, ALE 0.07, PME 0.07, PLE 0.07, AME–AME 0.04, PME–PME 0.06, AME–ALE, 0.03, PME–PLE 0.04, AME–PME 0.05, ALE–ALE 0.31, PLE–PLE 0.34, ALE–PLE contiguous. Length of legs: I 4 (1.15, 1.29, 1.01, 0.55), II 4 (1.14, 1.29, 0.99, 0.58), III 2.98 (0.89, 0.92, 0.76, 0.41), IV 3.73 (1.07, 1.16, 0.97, 0.51). Leg formula I-II-IV-III. Tm I and Tm IV present. Tibial spine formula: 2-2-1-1. Abdomen 1.63 long, 0.86 wide, oval, pale, mid dorsally with a longitudinal pale band followed by five transverse black chevrons, ventral side pale.

Epigyne ( Fig. 296B, 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 two coiled spirals extending anteriorly; 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 ).

Genus Stemonyphantes Menge, 1866 (ZƦø)

Figures

FIGURE 296. Sinisterigone rutundis sp. nov., female holotype. A Habitus, dorsal view B Epigyne, ventral view C Vulva, dorsal view.

FIGURE 297. Distribution of Sinisterigone gen. nov.