Hamus bowoensis, Ballarin & Li, 2015

Ballarin, Francesco & Li, Shu-Qiang, 2015, Three new genera of the family Nesticidae (Arachnida: Araneae) from Tibet and Yunnan, China, Zoological Systematics 40 (2), pp. 179-190 : 180-183

Hamus bowoensis sp. nov. ( Figs 1–2 , 7 )

Material examined. Holotype ♂, 30 August 2010, China, Tibet, Nyingchi, Bowo County (29°51'49.1754"N, 95°46'24.528"E), elev. 2 731 m. Paratypes 2 ♀, 12 August 2014, China, Tibet, Nyingchi, Bowo County, Yigong Town , Kaduo Village (30°7'30.9"N, 95°1'55.6788"E), elev. 2 072 m, leg. Yun-Chun Li.

Etymology. The specific name is derived from the type locality; adjective.

Diagnosis. The new species can be easily recognized by the shape of the male palpal cymbium with a large cymbial furrow, by the general appearance of the short paracymbium and its terminal hooked process and by the two massive hook-like processes of the terminal apophysis ( Figs 1A–D ). The two sclerotized processes at the base of the conductor, the

© Zoological Systematics, 40(2): 179–190

© Zoological Systematics, 40(2): 179–190

© Zoological Systematics, 40(2): 179–190 distally swollen palpal femur and the tuft of hair on the femur I are also helpful characters to separate males of H. bowoensis sp. nov. from the males of all the other known species. The general appearance of the epigyne ( Figs 2A, C ), with the large spermathecae visible through the tegument and the orientation of the insemination and fertilization ducts ( Fig. 2B ) are diagnostic to distinguish the female.

Description. Male (holotype). Total length 1.87. Carapace length 1.01, width 0.89. Leg formula: I, IV, II, III. Leg measurements: I: 1.34, 0.38, 1.27, 0.81, 0.71 (4.51); II: 1.13, 0.38, 1.02, 0.76, 0.77 (4.06); III: 0.92, 0.32, 0.67, 0.57, 0.59 (3.07), IV: 1.43, 0.38, 1.06, 0.74, 0.72 (4.33). Habitus as in Figs 2D, F . Prosoma approximately circular in dorsal view, uniformly yellow. Fovea visible as a deep depression. Cephalic area slightly raised but clearly distinct from the rest of the prosoma. Chelicera yellow with three teeth on the promargin. Clypeus, labium and sternum of the same color. Labium rebordered. Legs uniformly yellow, femur I with a tuft of hairs on the prolateral margin. Metatarsal trichobothrium position (TmI) = 0.4. Metatarsus IV with a ventral row of long, serrated bristles (tarsal comb). Opisthosoma gray with a faint, lanceolate lighter area. Ventral side uniformly light gray.

Palp ( Figs 1A–D ) uniformly yellow with a darker bulb, rounded and ventrally flat. Palpal femur distally swollen. Long lateral cymbial furrow (Lf) on the retrolateral side of the cymbium. Paracymbium short, transversally oriented to the cymbium and ending with a flat, transparent lobe and a short, hooked distal process (Dp). A small, blunt dorsal apophysis (Da) and a lobed ventral apophysis (Va) are present. Terminal apophysis strongly sclerotized with a flat, rounded base and two hooked processes (Ta-I, Ta-II) ventrally and inward oriented forming a C-like structure. Tegular apophysis not visible. Embolus (E) filamentous, starting from the left side of the palp and continuing with a circular, clockwise course bordering the subtegulum and ending in centre of the bulb. Conductor (C) shaped as a long plate, starting in the frontal part of the bulb and following the embolus on the prolateral side with a counterclockwise course. A hooked, blunt process (Cp-I) is present on the frontal margin; a second, elongated process (Cp-II) is bended ventrally and leading the terminal part of the embolus in the center of the bulb near the tip of the Ta-II.

Female (one of the paratypes). Total length 2.15. Carapace length 1.08, width 0.89. Leg formula: I, IV, II, III . Leg measurements: I: 1.39, 0.41, 1.21, 0.87, 0.71 (4.59); II : 1.18, 0.39, 0.93, 0.72, 0.67 (3.89); III: 0.93, 0.36, 0.67, 0.56, 0.58 (3.10); IV: 1.34, 0.4, 1.11, 0.76, 0.69 (4.3). Habitus as in Fig. 2E . Prosoma oval in dorsal view. Palp with a long pectinate claw. Femur I without the tuft of hairs. All other characters as in the male .

Epigyne and vulva as in the Figs 2A–C . Posterior edge of the epigynal plate (Ep) slightly sclerotized. Spermathecae (S) and insemination ducts (Id) can be observed through the tegument. Insemination ducts making a large, flat spiral before reaching the spermathecae with several coils. Fertilization ducts (Fd) short and ventrally oriented. Spermathecae very large, oval and close to each other.

Habitat. Litter of mountain forests over 2 000 m.

Distribution. Known only from the type locality.

Figures

Fig. 1. Hamus bowoensis sp. nov., male palp. A. Dorsal view. B. Ventral view. C. Prolateral view. D. Retrolateral view. Scale bars= 0.1 mm.

Fig. 2. Hamus bowoensis sp. nov. A. Epigyne, ventral view. B. Vulva, dorsal view. C. Vulva, ventral view. D. Male habitus, dorsal view. E. Female habitus, dorsal view. F. Male habitus, lateral view. Scale bars: A–C =0.1mm; D–F =0.5mm.

Fig. 7. Locality records of three new species of the family Nesticidae from China.