Belisana mengyang Zhu & Yao & Zheng & Li 2020, sp. nov.

Belisana mengyang Yao & Li sp. nov.

Figs 5–6

Type material. Holotype: Male (IZCAS Ar39748), seasonal rain forest (22°09’45.9”N, 100°52’33.2”E, elevation 862 ± 33 m), Mengyang County, Xishuangbanna, Yunnan, China, 22 July 2012, Q. Zhao and Z. Chen leg. Paratypes: 5 males (IZCAS Ar39749–Ar39753) and 2 females (IZCAS Ar39754–Ar39755), same data as holotype.

Etymology. The specific name refers to the type locality and is a noun in apposition.

Diagnosis. This species resembles B. cas Yao & Li, 2018 (see Yao et al. 2018: 250, figs 7–8, 11D, 12D) with similar male chelicerae (Fig. 6C) and bulbal apophyses (Fig. 6D) but can be distinguished by presence of curved prolateral sclerite distally (arrow 1 in Fig. 5C) and large retrolateral membranous process distally (arrow 2 in Fig. 5C) on procursus, dorsally strongly protruding procursus (arrow in Fig. 5A), unmodified male pedipalpal coxa (Fig. 5B). The female is recognised by presence of subcuticular teeth on epigynum (Fig. 6A), slightly separated vulval pore plates (Fig. 6B) and by absence of serrated sclerites on vulva (Fig. 6B).

Description. Male (holotype). Total length 1.39 (1.48 with clypeus), carapace 0.53 long, 0.52 wide, opisthosoma 0.86 long, 0.55 wide. Leg I: 10.06 (3.60 + 0.31 + 1.40 + 2.25 + 2.50), leg II: 7.64 (2.50 + 0.31 + 2.19 + 1.88 + 0.76), leg III: 6.20 (1.60 + 0.31 + 1.25 + 2.50 + 0.54), leg IV: 8.60 (2.50 + 0.25 + 2.00 + 3.20 + 0.65); tibia I L/d: 39. Habitus as in Figs 6 E–F. Carapace and sternum pale, without marks. Legs pale, without darker rings. Opisthosoma pale, without spots. Distance PME-PME 0.08, diameter PME 0.05, distance PME-ALE 0.03, AME absent. Ocular area not elevated. Thoracic furrow absent. Clypeus unmodified. Sternum approximately as wide as long (0.44). Chelicerae (Fig. 6C) with pair of small proximo-lateral apophyses and pair of short distal apophyses (distance between tips: 0.14). Pedipalps as in Figs 5 A–B; coxa unmodified; trochanter with short retrolatero-ventral apophysis (arrow in Fig. 5B); femur without dorsal apophysis proximally; procursus (Figs 5 A–D) simple proximally and complex distally, strongly protruding subdistally (arrow in Fig. 5A), with curved prolateral sclerite distally (arrow 1 in Fig. 5C) and large retrolateral membranous process distally (arrow 2 in Fig. 5C); bulb (Fig. 6D) with hooked apophysis and simple embolus. Retrolateral trichobothria of tibia I at 23% proximally; legs with short vertical setae on metatarsi, without spines and curved setae; tarsus I with 12 distinct pseudosegments.

Female (IZCAS Ar39754): Similar to male, habitus as in Figs 6 G–H. Total length 1.55 (1.65 with clypeus), carapace 0.67 long, 0.63 wide, opisthosoma 0.88 long, 0.65 wide; tibia I: 1.37; tibia I L/d: 35. Distance PME-PME 0.09, diameter PME 0.05, distance PME-ALE 0.03, AME absent. Sternum approximately as wide as long (0.56). Epigynum (Fig. 6A) simple and flat, with pair of pockets 0.12 apart (ep in Figs 6 A–B) and several subcuticular teeth. Vulva (Fig. 6B) with curved anterior arch and pair of strongly curved pore plates.

Variation: Tibia I in four male paratypes (IZCAS Ar39749–Ar39752; leg I missing in IZCAS Ar39753): 1.33, 1.35, 1.37, 1.43. Tibia I in another female paratype (IZCAS Ar39755): 1.40.

Distribution. China (Yunnan, type locality; Fig. 7).