Belisana bachma Zhu & Li 2021, sp. nov.

Belisana bachma sp. nov.

Figs 1–2, 13A–B, 14A–B, 15A

Type material. Holotype: Male (IZCAS Ar41901), Bach Ma National Park (16°13’45.78”N, 107°50’53.46”E, elevation 371 m), Thua Thien Hue, Vietnam, 27 August 2015, D.S. Pham leg. Paratypes: 1 male (IZCAS Ar41902) and 1 female (IZCAS Ar41903), same data as holotype.

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

Diagnosis. This species resembles B. babensis Yao, Pham & Li, 2015 (see Yao et al. 2015: 5, figs 1–3) with the elongated bulbal apophyses (Fig. 2D) and vulval anterior arch of a similar dark internal shade (Figs 2B, 14B), but males can be distinguished by the presence of a strongly conical subdisto-dorsally protruding (arrow in Fig. 1A) and bifid disto-prolateral spine (arrow 1 in Figs 1C, 13A) on the procursus, by the presence of a frontal apophysis (arrow in Fig. 2E) and a pair of small ventral apophyses (arrow in Fig. 2C) on the clypeus, and the cheliceral distal apophyses are directed laterally (arrow da in Figs. 2C, 15A; distal apophyses directed anteriorly in B. babensis). Females can be distinguished by having frontal “epigynal” pockets laterally on a sclerotized plate (arrow ep in Figs 2A–B, 14A–B) and the vulval pore plates are approximately as wide as long (arrow pp in Figs 2B, 14B).

Description. Male (holotype, IZCAS Ar41901): Total length 2.01 (2.16 with clypeus), carapace 0.98 long, 0.65 wide, opisthosoma 1.18 long, 0.80 wide. Leg I: 16.89 (4.55 + 0.19 + 4.42 + 6.67 + 1.15), leg II: 11.08 (3.21 + 0.18 + 2.75 + 4.17 + 0.77), leg III: 7.40 (2.24 + 0.16 + 1.86 + 2.56 + 0.58), leg IV: 10.61 (3.14 + 0.17 + 2.69 + 3.97 + 0.64); tibia I L/d: 55. Distance PME-PME 0.17, diameter PME 0.08, distance PME-ALE 0.11, AME absent. Habitus as in Figs 2E–F. Carapace pale, with brown lateral margins. Ocular area with indistinct dark marks and not elevated. Clypeus brown, with frontal apophysis (arrow in Fig. 2E) and pair of small ventral apophyses (arrow in Fig. 2C). Chelicerae (Figs. 2C, 15A) with pair of small proximo-lateral apophyses and pair of long, curved distal apophyses, each with sclerotized and pointed tip (distance between tips of distal apophyses: 0.38). Sternum pale, approximately as wide as long (0.50). Thoracic furrow absent. Legs pale. Opisthosoma pale, with indistinct large spots. Palp as in Figs 1A–B; coxa unmodified; trochanter with short ventral apophysis with small retrolateral apophysis (arrow 1 in Fig. 1B); femur with small proximo-dorsal apophysis (arrow 2 in Fig. 1B); procursus (Figs 1A–D, 13A–B) simple proximally but complex distally, strongly protruding subdisto-dorsally (arrow in Fig. 1A), with bifid disto-prolateral spine (arrow 1 in Figs 1C, 13A), large, curved subdisto-prolateral sclerite (arrow 2 in Figs 1C, 13A), disto-retrolateral membranous lamella (arrow in Figs 1D, 13B) and tongue-shaped retrolateral flap (arrow f in Figs 1D, 13B); bulb (Fig. 2D) with hooked apophysis and simple embolus. Retrolateral trichobothria of tibia Iat 6% proximally; legs with short, vertical setae on metatarsi, without spines or curved setae; tarsus Iwith 11 distinct pseudopodomeres.

Female (IZCAS Ar41903): Similar to male, habitus as in Figs 2G–H. Total length 2.19 (2.32 with clypeus), carapace 0.75 long, 0.63 wide, opisthosoma 1.16 long, 0.81 wide. Tibia I: 3.70; tibia I L/d: 46. Distance PME-PME 0.13, diameter PME 0.08, distance PME-ALE 0.09, AME absent. Sternum approximately as wide as long (0.56). Ocular area without marks. External female genitalia (Figs 2A, 14A) simple and flat, with pair of frontal “epigynal” pockets (arrow ep in Figs 2A–B, 14A–B), 0.48 apart. Vulva (Figs 2B, 14B) with W-shaped anterior arch (median ridge strongly protruding, arrow in Figs 2B, 14B) and pair of large, nearly trapezoidal pore plates (arrow pp in Figs 2B, 16B), without serrated sclerites.

Variation: Tibia Iin another male (IZCAS Ar41902): 4.47.

Natural history. The species was found in leaf litter and collected by small plot direct searching.

Distribution. Vietnam (Thua Thien Hue, type locality only; Fig. 16).