Utivarachna lata, Jin, Chi, Yin, Xiangchu & Zhang, Feng, 2015

Jin, Chi, Yin, Xiangchu & Zhang, Feng, 2015, A new species of the genus Utivarachna Kishida, 1940 (Araneae: Trachelidae) from China, with the first description of the male of U. fabaria Zhao & Peng, 2014 and a redescription of U. gui (Zhu, Song & Kim, 1998), Zootaxa 4057 (4), pp. 569-581 : 570-573

Utivarachna lata sp. nov.

Figs 1–3

Type material. Holotype: ♂, CHINA: Guizhou Province: Chishui City, Yuanhou Township, Datang Village, Mt. Wuzhufeng (28°23.448′N, 105°58.690′E), 1073m a.s.l., 2 October 2012, leg. Luyu Wang. Paratypes: 1♀, same data as holotype; 8♀, CHINA: Guizhou Province: Shibing County, Mt. Yuntai (27°06.360′ N, 108°06.547′ E), 926m a.s.l., 19 October 2012, leg. Luyu Wang and Xuankong Jiang. Sichuan Province: 2♀, Nanjiang County, Mt. Guangwu, Taoyuan Scenic (32°39.691′ N, 106°50.757′ E), 1263m a.s.l., 6 August 2014, leg. Shanjie Zha.

Etymology. The specific name comes from the Latin word “latus”, which means wide, and refers the wide embolus coils.

Diagnosis. Among the species of the kinabaluensis group, the male of this new species resembles U. bucculenta Deeleman-Reinhold, 2001 in having similar embolus coils that are oblique and as wide as the genital bulb, but can be distinguished from it by: 1) the palpal retrolateral tibial apophysal apex with a small hook instead of a claw, whereas the apophysal claw is long and S-shaped in the latter; 2) the terminal portion of embolus is twisted, whereas it is not twisted in U. bucculenta ; 3) the legs lack bands and ventral cusps, whereas the legs are distinctly banded and the anterior tibiae, metatarsi and tarsi have ventral cusps in U. bucculenta . The female is similar to U. taiwanica Hayashi & Yoshida, 1993 in having a large epigynal atrium and the copulatory duct coiled three times posteriorly, but can be distinguished from the latter by: 1) the anterior part of copulatory ducts are thicker than in the latter; 2) the connecting ducts are slightly curved and clearly visible in dorsal view, whereas they are straight and covered by the bursae in U. taiwanica ; 3) the spermathecae are large and separated by approximately half a spermatheca’s diameter, whereas they are relatively small and separated by almost twice a spermatheca’s diameter in U. taiwanica .

Description. Male. Holotype ( Fig. 1 A): total length 5.52. Carapace: 2.96 long, 2.26 wide. Opisthosoma: 2.56 long, 2.05 wide. Eye sizes and interdistances: AME 0.16, ALE 0.18, PME 0.15, PLE 0.17, AME–AME 0.09, AME–ALE 0.12, PME–PME 0.26, PME–PLE 0.33, ALE–PLE 0.30. MOA 0.42 long, anterior width 0.43, posterior width 0.57. AER nearly straight, PER recurved, wider posteriorly. Clypeus height 0.16. Chelicerae coloured as carapace, with three promarginal and five retromarginal teeth. Carapace black, surface rough, with white hairs. Fovea dark, longitudinal and short. Sternum dark reddish brown with sparse white hairs. Labium longer than wide. Legs brown, without ventral cusps ( Figs 1 C–D), metatarsi III–IV distally with preening brushes ventrally. Leg measurements: I 6.39 (1.89, 0.91, 1.49, 1.26, 0.84), II 5.99 (1.79, 0.88, 1.28, 1.24, 0.80), III 4.80 (1.40, 0.73, 0.88, 1.24, 0.55), IV 6.11 (1.69, 0.75, 1.31, 1.70, 0.66), formula: 1423. Opisthosoma ovoid with short brown hairs; anterior two-thirds with a wide dorsum. Dorsum yellowish brown, with several transverse, archshaped, lightly coloured markings from posterior margin of dorsal scutum to anal tubercle; dorsal scutum oval, brown, lightly sclerotized, with two pairs of muscular impressions, posterior margin truncated. Venter coloured as dorsum, with longitudinal rows of sclerotized spots.

Palp ( Figs 2 A–D, 3D–F). The apex of the retrolateral tibial apophysis bears a small, sharp hook. Genital bulb nearly rectangular, longer than wide. Tegulum mostly membranous. In ventral view, the visible sperm duct is short, straight and sickle-shaped from retrolateral view. Subtegulum strongly sclerotized, clearly visible in ventral view. Embolus coils oblique, as wide as genital bulb; embolus originating from posterior portion of genital bulb; terminal portion of embolus twisted, S-shaped, resting in distal cymbial alveolus.

Female. Total length 4.40–6.05 (n=11). Paratype ( Fig. 1 B): total length 5.90. Carapace 2.97 long, 2.91 wide. Opisthosoma: 2.93 long, 2.29 wide. Eye sizes and interdistances: AME 0.15, ALE 0.18, PME 0.15, PLE 0.16, AME–AME 0.09, AME–ALE 0.12, PME–PME 0.24, PME–PLE 0.33, ALE–PLE 0.34. MOA 0.38 long, anterior width 0.40, posterior width 0.57. Clypeus height 0.13. Leg measurements: I 5.91 (1.75, 0.83, 1.36, 1.22, 0.75), II 5.61 (1.58, 0.82, 1.28, 1.22, 0.71), III 4.69 (1.32, 0.72, 0.87, 1.17, 0.61), IV 5.76 (1.73, 0.77, 1.37, 1.20, 0.69), formula: 1423. Opisthosoma dorsum blackish grey, lacking dorsal scutum, with several transverse, arch-shaped, lightly coloured markings from median portion to anal tubercle. Other characters as in male.

Epigyne ( Figs 2 E, 3A): atrium large, posteriorly located, wider than outermost edges of spermathecae; copulatory openings large and round, situated at anterior margin of epigyne. Vulva ( Figs 2 F, 3B–C): copulatory duct long, coiled three times around the anterior of connecting duct, anteriorly wide and posteriorly narrower; connecting ducts slender, slightly curved; bursae clavate, anterior portion slightly constricted, posterior end very close to spermathecae and with defined patches that may be gland pores; spermathecae spherical, located posteriorly, separated by approximately half a spermatheca’s diameter.

Distribution. Known only from the type locality ( Fig. 9 ).

Figures

FIGURE 1. Utivarachna lata sp. nov., A. male habitus, dorsal view; B. female habitus, dorsal view; C. male leg I, retrolateral view; D. male leg II, retrolateral view. Scale bars: 2 mm (A – B); 1 mm (C – D).

FIGURE 2. Utivarachna lata sp. nov., A. male left palp, prolateral view; B. same, dorsal view; C. same, retrolateral view; D. same, ventral view; E. epigyne, ventral view; F. vulva, dorsal view. Scale bars: 0.5 mm.

FIGURE 3. Utivarachna lata sp. nov., A. epigyne, ventral view; B. vulva, dorsal view; C. schematic of internal duct system; D. male left palp, prolateral view; E. same, ventral view; F. same, retrolateral view. Scale bars: 0.5 mm (A – B, D – F); 0.25 mm (C).

FIGURE 9. Distribution of Utivarachna lata sp. nov., U. fabaria Zhao & Peng, 2014 and U. gui (Zhu, Song & Kim, 1998).