Pholcus cheni Yao & Li, 2017

Dong, Tingting, Zheng, Guo, Yao, Zhiyuan & Li, Shuqiang, 2017, Ten new species of the spider genus Pholcus Walckenaer, 1805 (Araneae, Pholcidae) from Southeast Asia, Zootaxa 4306 (3), pp. 339-369 : 357

Pholcus cheni Yao & Li sp. nov.

Figs 13–14

Type material. Holotype: male (Ar29665), Sumano Cave (7°35.172′N, 99°52.078′E, elevation 76 m), Srinakarind District , Rattalung, Thailand, 27 October 2015, Q. Zhao, G. Zhou and Z. Chen leg. Paratypes: 2 males and 2 females (Ar 29666–29669), same data as holotype.

Etymology. The specific name is a patronym in honor of the collector Z. Chen; noun (name) in genitive case.

Diagnosis. This species resembles P. khaolek Huber, 2016 (see Huber et al. 2016c: 21, figs 52–53, 63–78, 99– 101) with similar male chelicerae ( Fig. 14 D), procursus ( Figs 13 C–D), bulbal apophyses ( Fig. 14 C) and epigynum ( Fig. 14 A) but can be distinguished by the male pedipalp trochanter apophysis broad proximally but very narrow distally ( Fig. 13 B), by the anterior arch heavily sclerotized medially on the vulva (arrow in Fig. 14 B) and by the more separated pore plates ( Fig. 14 B).

Description. Male (holotype): Total length Total length 4.40 (4.74 with clypeus), carapace 1.28 long, 1.44 wide, opisthosoma 3.12 long, 1.38 wide. Leg I: 54.71 (12.69 + 0.63 + 13.27 + 26.09 + 2.03), leg II: – (9.17 + 0.63 + 8.97 + 15.06 + –), leg III: – (6.09 + 0.58 + – + – + –), leg IV: 28.23 (8.72 + 0.63 + 5.75 + 11.93 + 1.20); tibia I L/ d: 104. Distance PME-PME 0.34; diameter PME 0.10; distance PME-ALE 0.04; distance AME-AME 0.05; diameter AME 0.06. Sternum wider than long (0.94/0.70). Habitus as in Figs 14 E–F. Carapace yellowish, with brown marks on posterior half; ocular area yellowish; sternum yellowish, with brownish marks. Legs yellowish, patellae, distal parts of tibiae and proximal part of metatarsi dark brown, without darker rings. Opisthosoma yellowish, without spots. Ocular area elevated, each eye triad on top of a laterally directed eye-stalk, and provided with modified setae. Thoracic furrow absent. Chelicerae as in Fig. 14 D, with a pair of proximo-lateral apophyses, a pair of distal apophyses, each with two cone-shaped teeth, and a pair of frontal apophyses. Pedipalps as in Figs 13 A–B; trochanter with a long and large ventral apophysis, broad proximally but very narrow distally; femur proximally widened on ventral side, with a dorsal apophysis proximally (arrow in Fig. 13 B); procursus simple proximally but complex distally, with a membranous, fringed prolateral process subdistally (arrow in Fig. 13 D); bulbal apophyses as in Fig. 14 C; uncus with a scaly edge; appendix swollen distally, with a retrolateral apophysis subdistally; embolus weakly sclerotized. Retrolateral trichobothrium of tibia I at 7%; legs with short vertical setae on tibiae, metatarsi and tarsi; without spines and curved setae; tarsus I with 14 distinct pseudosegments.

Female: Similar to male, habitus as in Figs 14 G–H. Total length 4.09 (4.49 with clypeus), carapace 1.12 long, 1.30 wide, opisthosoma 2.97 long, 1.31 wide; tibia I: 9.74; tibia I L/d: 70. Distance PME-PME 0.22; diameter PME 0.11; distance PME-ALE 0.03; distance AME-AME 0.03; diameter AME 0.05. Sternum wider than long (0.83/ 0.69). Ocular area without eye-stalks. Epigynum ( Fig. 14 A) with a knob. Vulva ( Fig. 14 B) with a medially heavily sclerotized anterior arch and two nearly elliptic pore plates.

Variation: Tibia I in male paratype (n=1, leg I lost in the other specimen): 13.85. Tibia I in another female paratype: 9.42.

Distribution. Thailand (Rattalung, type locality; Fig. 21 ).

Natural History. The species was found in the entrance zone of the cave.

Figures

FIGURE 13. Pholcus cheni Yao & Li sp. nov., holotype male. A – B. Pedipalp (A. Prolateral view; B. Retrolateral view, arrow points at dorsal apophysis on femur proximally); C – D. Distal part of procursus (C. Prolateral view; D. Dorsal view, arrow points at membranous, fringed prolateral process). a = appendix, b = bulb, e = embolus, pr = procursus, u = uncus. Scale bars: 0.20 (A – B), 0.05 (C), 0.03 (D).

FIGURE 14. Pholcus cheni Yao & Li sp. nov., holotype male (C – F) and paratype female (A – B, G – H). A. Epigynum, ventral view; B. Vulva, dorsal view, arrow points at heavily sclerotiZed anterior arch medially; C. Bulbal apophyses, prolateral view; D. Chelicerae, frontal view; E – H. Habitus (E, G. Dorsal view; F. Lateral view; H. Ventral view). a = appendix, da = distal apophysis, e = embolus, fa = frontal apophysis, pa = proximo-lateral apophysis, pp = pore plate, u = uncus. Scale bars: 0.10 (A – B, D), 0.05 (C), 0.50 (E – H).

FIGURE 21. Distribution records of new Pholcus species from Southeast Asia. 1. Pholcus bulacanensis Yao & Li sp. nov. from the P. bicornutus species group; 2. P. duan Yao & Li sp. nov., 3. P. ping Yao & Li sp. nov. and 4. P. vietnamensis Yao & Li sp. nov. from the P. bidentatus species group; 5. P. fuza Yao & Li sp. nov. and 6. P. mueangensis Yao & Li sp. nov. from the P. buatong species group; 7. P. cheni Yao & Li sp. nov. and 8. P. subwan Yao & Li sp. nov. from the P. halabala species group; 9. P. shuye Yao & Li sp. nov. from the P. krabi species group; 10. P. dongxue Yao & Li sp. nov. from the P. yichengicus species group.