Pachygnatha shengtangensis Huang, Wu, Yin, Xu & Chen, 2024, sp. nov.
Creators: name: Huang, Zongguang
name: Wu, Yecheng
name: Yin, Haiqiang
name: Xu, Xiang
name: Chen, Junhao
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Tetragnathidae
Pachygnatha
Pachygnatha shengtangensis

description: Pachygnatha shengtangensis sp. nov.
(Î堂ḋşƍ)
Figures 1–6, 13A, B 14A, 15A, B, 16
Material examined. China: Guangxi Zhuang Autonomous Region: Laibin City, Jinxiu Yao Autonomous County, Shengtangshan Mountains, 23°58′3″N, 110°6′32″E, 1523 m, holotype ♂, 11 October 2021, leg. Ailan He, Jinxin Liu, Zongguang Huang, Rongrong Liao, Qin Li, Xuemei Yang, Yingli Wen, Zhao Ye and Yang Liu (HNU1067); Same collecting information as for holotype, paratypes 1♂ 3♀ (HNU502–505).
Etymology. The specific epithet is derived from the type locality, Shengtangshan Mountains, Guangxi, China.
Diagnosis. Pachygnatha shengtangensis sp. nov. resembles P. fengzhen in having a coiled embolus and a twisting conductor in males (Figs 2A, B, 3A, B; Zhu et al. 2003, fig. 43D, E), and curved spermathecae in female (Figs 5B, 6A; Zhu et al. 2003, fig. 42F), but the new species can be distinguished from P. fengzhen by the ratio of width to length of carapace in both male and female (0.75 in the new species, versus 0.56 in P. fengzhen) (Figs 1A, 4A vs. in Zhu et al. 2003, fig. 42A) and the shape of distal ends of the paracymbium and nuptial spur in male (blunt in the new species, versus sharp in P. fengzhen) (Figs 2B, 3B, 2D, 3D vs. Zhu et al., 2003, fig. 43A, F).
Pachygnatha shengtangensis sp. nov. is also similar to P. amurensis and P. tenera in the shapes of embolus, conductor in male (Figs 2A, B, 3A, B; Zhu et al. 2003, figs 45D, E, 49D, E) and the shape of spermathecae in female (Figs 5B, 6A; Zhu et al. 2003, figs 44G, 48G), but the new species can be distinguished from the latter two by the number and arrangement of cheliceral teeth on the promargin, and the dorsal trichobothria on femur IV in both male and female (The new species has five promarginal teeth, with the first tooth positioned near the distal end of the chelicera and the remaining four teeth arranged in the middle portion while P. amurensis has three, all positioned in the middle part of the chelicera, and P. tenera has three, with the last two teeth located closer to the base of the chelicera. Two trichobothria in the new species, versus three teeth and just one trichobothrium in P. amurensis and P. tenera) (Figs 2D, E, 8D, E; Zhu et al. 2003, figs 44C, 45A, 48C, 49A; see Fig. 15A, B and the description in Zhu et al. 2003: 100, 105).
Description. Male. Holotype (HNU1067). Total length 3.11. Carapace 1.42 long, 1.10 wide, pear-shaped, dark brown (Fig. 1A). Head area much higher than thoracic area and eyes are surrounded by black ocular tubercles (Fig. 1A, C). Cervical groove and radial groove obvious and black (Fig. 1A). Fovea arc-shaped (Fig. 1A). Chelicerae dark brown, with five promarginal and four retromarginal teeth, accompanied by a nuptial spur on the prolateral surface (Figs 2D, E, 3D, E). Promarginal teeth approximately equal in size, with the first tooth near the fang base and far from others (Figs 2D, 3D). The first and second teeth in the retromargin far away from each other and both much larger than the other two (Figs 2E, 3E). Fang with a slightly bend in its longitudinal midsection (Figs 2D–F, 3D–F). Labium trapezoidal, wider than long, with the anterior margin thickened (Fig. 1B). Maxilla far longer than wide (Fig. 1B). Sternum 0.82 long, 0.98 wide, same color as the medial portion of the carapace, with a lot of small pits, and bilaterally and posteriorly extending between coxae (Fig. 1B). Eyes subequal in size. ALE and PLE close together, slightly smaller than the median eyes. Eye sizes and inter-distances: ALE 0.11; AME 0.12; PLE 0.10; PME 0.13; ALE-AME 0.11; AME-AME 0.10; PLE-PME 0.12; PME-PME 0.19; MOA length 0.27, anterior width 0.31, posterior width 0.36 (Fig. 1A). Legs long and slender, brown. Femur IV with two dorsal trichobothria (Fig. 15A). Leg measurements: Ⅰ 7.19 (1.88, 0.51, 2.04, 1.74, 1.02); II 6.29 (1.74, 0.46, 1.72, 1.50, 0.87); III 3.83 (1.16, 0.36, 0.84, 0.88, 0.59); IV 4.99 (1.50, 0.36, 1.22, 1.21, 0.70). Abdomen: 1.67 long, 1.29 wide, oval, featuring transverse irregular or chevron stripes on the dorsal surface, along with several guanine silvery patches present in the dorsal, lateral and ventral surfaces (Fig. 1).
Pedipalp (Figs 2, 3, 13A, B, 14A). Tibia twice as long as wide in the ventral side, with the dorsal side significantly longer than the ventral side (Figs 2A, C, 3A, C). Paracymbium stick-shaped, with a blunt distal end and a small curved apophysis located in the middle (Figs 2B, 3B). Cymbium strongly constricted at its midsection (Figs 2C, 3C). Embolus coiled for about one circle around the tegulum, with its distal third extending towards the top of cymbium and nearly parallel to the distal portion of cymbium. Embolic medial groove (EMg) conspicuous, dividing the basal part of embolus into two sclerotised parts that coil more than half a turn, creating the illusion of two concentric circles (Figs 2A, 3A, 13A, B, 14A). Conductor well-developed, comprising a transverse cutinized part and a vertical spiral membranous part when viewed from above (Figs 13A, B, 14A).
Female (HNU502). Somatic morphology similar to male (Fig.4). Total length 2.95. Carapace 1.34 long, 1.05 wide. Sternum 0.87 long, 0.92 wide. Eye sizes and inter-distances:ALE 0.09; AME 0.10; PLE 0.09; PME 0.12; ALE-AME 0.17; AME-AME 0.14; PLE-PME 0.15; PME-PME 0.19; MOA length 0.30, anterior width 0.29, posterior width 0.35. Chelicera promargin with five teeth and almost consitsant space between the front and rear teeth (Figs 5C, D, 6B, C). Retromarginal teeth as same as male (Figs 5D, E, 6C, D). Fang straight, not as in males (Figs 5C–E, 6C–E). Femur IV with two dorsal trichobothria (Fig. 15B). Leg measurements: Ⅰ 7.02 (1.84, 0.50, 1.92, 1.69, 1.07); II 6.02 (1.64, 0.43, 1.63, 1.43, 0.89); III 3.53 (0.97, 0.32, 0.80, 0.86, 0.58); IV 4.66 (1.41, 0.34, 1.16, 1.13, 0.62). Abdomen: 1.66 long, 1.06 wide.
Female genitalia(Figs5A,B, 6A).Genital fold1.8times wider than long.Gonopore crevice-shaped.Spermathecae kidney-shaped, far away from each other (at least more than twice the widest diameter of spermatheca). Uterus externus smooth.
Distribution: Known only from the type locality, China (Guangxi) (Fig. 16).
description: Published as part of Huang, Zongguang, Wu, Yecheng, Yin, Haiqiang, Xu, Xiang & Chen, Junhao, 2024, Two new species of the long-jawed orb-weaving spider genus Pachygnatha Sundevall, 1823 (Araneae, Tetragnathidae) from southern China, pp. 385-406 in Zootaxa 5555 (3) on pages 388-393, DOI: 10.11646/zootaxa.5555.3.4, http://zenodo.org/record/14594782