Sinopoda abstrusa sp. nov.

Figs 1–3, 62

urn:lsid:zoobank.org:act: 7F9DBB72-5359-4C03-9EC4-1D66624E4320

Material examined. Holotype male: CHINA: Xizang Autonomous Region: Shannan City, Jiacha County, Anrao Town, 29.14°N, 92.59°E, near road, 20 July 2017, J. Chen, F.X. Liu, J. Liu & M. Fang leg. (CBEE). Paratypes: 1 male and 1 female (CBEE), 1 female (SMF), with same data as holotype .

Etymology. The specific name is derived from the Latin adjective abstrusus, -a, - um, meaning “invisible” referring to the inconspicuous (but present) glandular appendages of the vulva.

Diagnosis. Males of this species can be distinguished from other Sinopoda species by its unique vRTA developed as massive triangle in retrolateral view. Females are similar to those of Sinopoda scurion Jäger, 2012 (Jäger 2012: figs 61–65) in having glandular appendages inconspicuous in dorsal view, but can be distinguished from the latter by the following characters: 1. Epigynal field significantly wider than long (as wide as long in S. scurion); 2. Eight eyes present (eyes absent in S. scurion) (Figs 1 A–F, 2A–D, 3A–B).

Description. Male (holotype): Measurements: PL 8.6, PW 8.4; AW 4.4; OL 9.5, OW 6.1. Eyes: AME 0.38, ALE 0.68, PME 0.39, PLE 0.74, AME–AME 0.24, AME–ALE 0.06, PME–PME 0.54, PME–PLE 1.13, AME–PME 0.71, ALE–PLE 0.85, CH AME 0.26, CH ALE 0.34. Spination: Palp: 131, 101, 2121; Fe: I–III 323, IV 321; Pa: I–IV 001; Ti: I–III 2226, IV 2126; Mt: I 0 0 0 4, II 1014, III 2014, IV 2034. Measurements of palp and legs: Palp 13.0 (4.4, 1.6, 2.4, –, 4.6); I 46.4 (12.6, 3.1, 13.7, 13.4, 3.6); II 51.2 (14.2, 3.5, 15.5, 14.6, 3.4); III 39.9 (11.8, 3.4, 11.2, 10.6, 2.9); IV 41.8 (11.7, 3.2, 11.6, 12.0, 3.3). Leg formula: II-I-IV-III. Cheliceral furrow with 3 anterior, 4 posterior teeth and ca. 35 denticles.

Palp as in diagnosis. Cymbium distinctly longer than tibia. Embolus arising from tegulum at 6:30 to 7-o’clockposition in ventral view, with embolus tip as long as embolic apophysis. Distal part of the embolus including the embolic apophysis bent at an acute angle. Spermophor almost straight in ventral view. RTA arising medially to proximally from tibia. dRTA slender, finger-shaped, touching vRTA almost at dorsal apex (Figs 1 A–C, 2A–D).

Colouration in ethanol. Dorsal prosoma yellowish-brown, lateral margins dark, with yellow submarginal transversal light band posteriorly. Fovea and radial furrows distinctly marked. Labium and gnathocoxae brown, both with distal parts brighter. Sternum yellowish-brown, with margin brown. Chelicerae deep reddish-brown. Legs yellowish-brown with dark spots. Dorsal opisthosoma yellowish-brown, covered by brown hairs, with three pairs of dark patches laterally. Ventral opisthosoma yellowish-brown (Figs 2 E–F).

Female: Measurements: PL 7.5, PW 7.4; AW 3.9; OL 7.8, OW 4.4. Eyes:AME 0.39, ALE 0.69, PME 0.46, PLE 0.66, AME–AME 0.28, AME–ALE 0.08, PME–PME 0.47, PME–PLE 1.02, AME–PME 0.66, ALE–PLE 0.74, CH AME 0.19, CH ALE 0.23. Spination: Palp: 131, 101, 2121, 1014; Fe: I–III 323, IV 321; Pa: I–IV 001; Ti: I–III 2026, IV 2126; Mt: I–II 0 0 0 4, III 2014, IV 3036. Measurements of palp and legs: Palp 10.4 (2.9, 1.4, 2.4, –, 3.7); I 31.7 (8.9, 3.3, 9.1, 8.0, 2.4); II 33.1 (10.1, 3.1, 10.1, 7.6, 2.2); III 28.7 (8.9, 2.3, 8.4, 6.8, 2.3); IV 29.6 (8.8, 2.1, 8.5, 7.9, 2.3). Leg formula: II-I-IV-III. Cheliceral furrow with 3 anterior, 4 posterior teeth and ca. 42 denticles.

Copulatory organ as in diagnosis. Additional anterior folds present, starting from anterior end of lobal septum to lateral margins of epigynal field. Glandular appendages situated ventrally, only visible in lateral view. Spermathecae elongated oval, parallel, touching each other along median line. Fertilization ducts arising posterio-laterally (Figs 1 D–F, 3A–B).

Colouration in ethanol. As in males (Figs 3 C–D).

Distribution. China (Xizang) (Fig. 62).