Pholcus musensis Yao & Li, sp. nov.

Pholcus musensis Yao & Li sp. nov.

Figs 27–28

Type material. Holotype: male, Wat Dearoop Song Cave 1 (14°33.708′N, 101°24.064′E, elevation 397 m), Musee Village, Pak Chong District, Nakhon Ratchasima, Thailand, 23 October 2014, H. Zhao, Y. Li and Z. Chen leg. Paratypes: 2 females, same data as holotype.

Etymology. The specific name refers to the type locality; adjective.

Diagnosis. This species resembles P. kaebyaiensis sp. nov. (Figs 25–26) and P. songkhonensis sp. nov. (Figs 29–30) in having similar male chelicerae (Fig. 28 D), uncus (Fig. 28 C), and female external genitalia (Fig. 28 A) but can be distinguished by the absence of branches on the appendix (Fig. 28 C), by the presence of a large, sclerotized retrolateral apophysis distally on the procursus (arrow in Fig. 27 D), by the anterior arch of the vulva not protruding medially (Fig. 28 B); also distinguished from P. songkhonensis sp. nov. by the short eye-stalks on male ocular area (as in P. zhuchuandiani sp. nov., cf. Fig. 31 E).

Description. Male (holotype): Total length 4.50 (4.87 with clypeus), carapace 1.22 long, 1.41 wide, opisthosoma 3.28 long, 1.03 wide. Leg I missing, leg II: 28.7 (7.82 + 0.64 + 7.30 +11.54 + 1.40), leg III: 20.77 (6.09 + 0.60 + 5.13 + 8.01 + 0.94), leg IV: 26.20 (7.69 + 0.56 + 6.41 + 10.34 + 1.20). Distance PME-PME 0.32; diameter PME 0.10; distance PME-ALE 0.03; distance AME-AME 0.05; diameter AME 0.06. Sternum wider than long (0.88/0.78). Habitus as in Figs 28 E–F. Carapace yellowish, with brown median line and indistinct yellow marks; ocular area yellowish; sternum yellowish, with whitish marks. Legs yellowish, distal parts of femora and tibiae whitish, darker rings absent. Opisthosoma yellowish, with whitish spots dorsally. Ocular area elevated; each eye triad on top of a short, laterally directed eye-stalk (as in P. zhuchuandiani sp. nov., cf. Fig. 31 E). Thoracic furrow absent. Chelicerae as in Fig. 28 D, with a pair of proximo-lateral apophyses, a pair of black distal apophyses, and a pair of small frontal apophyses. Pedipalps as in Figs 27 A–B; trochanter with a short ventral apophysis; femur with a distinct ventral modification; procursus with two prolatero-dorsal spines (arrows in Fig. 27 C), distally complex; uncus with a scaly edge; appendix hooked; embolus weakly sclerotized, with some transparent projections distally. Legs with short vertical setae on tibiae, metatarsi and tarsi; without spines and curved setae.

Female: Similar to male, habitus as in Figs 28 G–H. Total length 4.48 (4.87 with clypeus), carapace 1.16 long, 1.25 wide, opisthosoma 3.32 long, 1.31 wide; leg I missing in all females. Distance PME-PME 0.20; diameter PME 0.09; distance PME-ALE 0.03; distance AME-AME 0.03; diameter AME 0.05. Sternum wider than long (0.80/0.72). Opisthosoma with indistinct spots dorsally. External genitalia (Fig. 28 A) with a knob. Vulva (Fig. 28 B) with a sclerotized anterior arch and two nearly triangular pore plates.

Distribution. Thailand (Nakhon Ratchasima, type locality; Fig. 32).

Natural history. The species was found in the aphotic zone inside the cave.