Three new spider species of the genus Pholcus from the Taihang Mountains of China (Araneae, Pholcidae)

Abstract In this study, three new species belonging to the genus Pholcus, collected from a forest of the Taihang Mountains, P. R. China, are described under the names of Pholcus papillatus sp. n. (male, female), Pholcus curvus sp. n. (male, female) and Pholcus auricularis sp. n. (male, female).


Introduction
The spider family Pholcidae C. L. Koch, 1850 is the ninth largest spider family and, to date, 1461 species, belonging to 79 genera, have been reported (World Spider Catalog 2016). It has a worldwide distribution, but the highest diversity is concentrated in the tropical and subtropical regions. Pholcine spiders occupy a wide range of habitats in a variety of ecosystems, e.g., in buildings, under rocks, in caves, in leaf litter, and under leaves (Huber 2005a). Huber (2000Huber ( , 2001Huber ( , 2003aHuber ( , b, c, 2005bHuber ( , c, 2009aHuber ( , 2011b reported a large number of new species and revised many genera in this family. Based on cladistic analyses of morphological and molecular data and on qualitative character assessment (Huber 2011a;Dimitrov et al. 2013), Pholcidae was divided into five subfamilies: Arteminae Simon, 1893, Modisiminae Simon, 1893, Ninetinae Simon, 1890, Pholcinae C.L. Koch, 1850and Smeringopinae Simon, 1893; Pholcinae is the most species-rich subfamily.
Pholcus Walckenaer, 1805 is the largest genus in Pholcinae, with 318 described species which are mainly distributed in the Old World. Pholcus can be diagnosed by the following combination of characters: male chelicerae usually with three pairs of apophyses; bulb usually with uncus and appendix; epigynum usually strongly sclerotized and with 'knob' (Huber 2011b). These Pholcus spiders frequently live in houses, rock-crevices, caves and leaf litter, and most spin loose and irregular webs in sheltered areas. Recently, the genus has been studied by several scholars: Huber (2001) made a few taxonomic remarks; Dimitrov and Ribera (2007) and Dimitrov et al. (2008) revised and cladistically analyzed the Macaronesian Pholcus species; Zhang and Zhu (2009)  The spider genus Pholcus Walckenaer, 1805 exhibits a highly diversity in China. One hundred fifteen Pholcus species attached to nine species groups (P. halabala species group, P. ponticus species group, P. crypticolens species group, P. zham species group, P. bidentatus species group, P. nagasakiensis species group, P. yichengicus species group, P. taishan species group, and P. phungiformes species group) were recorded from China (Zhang and Zhu 2009;Tong and Ji 2010;Tong and Li 2010;Huber 2011b;Peng and Zhang 2011a, b;Yao and Li 2012;Liu and Tong 2015;World Spider Catalog 2016).
The Taihang Mountains are located in the northeastern China, between 34°34'N to 40°43'N and 110°14'E to 114°33'E. Fuping county, a county of Hebei Province, is located in the Taihang Mountains area. To explore the diversity of the arthropod in Fuping county, one survey was carried out in 2014. While examining the spider specimens collected from leaf litter in this survey, three new species belonging to Pholcus were found and are reported in the present paper. Detailed diagnosis, descriptions, and illustrations of these new taxa are presented.

Material and methods
All specimens were preserved in 75% ethanol and examined, drawn, and measured under a Nikon SMZ1500 stereomicroscope equipped with a drawing tube. Photographs were taken with a Leica M205A stereomicroscope equipped with a Leica DFC550 Camera and LAS software (Ver. 4.6). Male and female genitalia were examined and illustrated after dissection. Epigyna were removed and treated in 10% warm solution of potassium hydroxide (KOH) before illustration. Left pedipalpi of male spiders were illustrated, except as otherwise indicated. All measurements are given in millimeters. Eye sizes were measured as the maximum diameter of the lens in dorsal or frontal view. Leg measurements are given as total length (femur + patella + tibia + metatarsus + tarsus). Leg segments were measured on their dorsal side. Terminology and taxonomic descriptions follow Huber (2000Huber ( , 2009b.
The following abbreviations are used in the text:

Pholcus phungiformes species group
The P. phungiformes group is largely distributed in northeastern China and the Korean Peninsula. Most species of this group have the following characters: carapace with vivid pattern, abdomen cylindrical, male chelicerae with proximal apophyses frontally, male palpal tibia with prolatero-ventral modification, procursus with dorsal spines, appendix absent, sometimes with pseudo-appendix (apophysis arising from uncus rather than from bulb, near usual position of appendix), epigynum sclerotized, with knobshaped apophysis (Huber 2011). The pseudo-appendix of P. exilis auct, date, P. wuling auct, date, and P. chicheng auct, date, may be bifid, but the character needs further study. The three new Pholcus species are assigned as members of this group in possessing most of the characters of the P. phungiformes group. Etymology. The specific name is from Latin word "papillatus", in reference to the shape of epigynal apophysis; adjective.
Distribution. Only known from the type locality.
Remarks. The females also resemble P. foliaceus Peng & Zhang, 2013, but  Etymology. The specific name is from the Latin word "curvus", in reference to the shape of the palpal uncus; adjective.
Diagnosis. Distinguished by the S-shaped tip of uncus, the long and curve beakshaped tip of the procursus, the hat-shaped membranous projection near tip, the small and almost quadrate-shaped epigynal apophysis (Figs 5A-D, 7A-D, 6E, 8F).
Distribution. Only known from the type locality. Remarks. Among the P. phungiformes group, the new species resembles P. alloctospilus Zhu & Gong, 1991 and P. fengchen Zhang & Zhu, 2009, but can be distinguished from those by: the short and thick club-shaped projection on tip of procursus, chitinized plate of the epigynum triangular arch (Figs 9C-D, 10E, 11C-D, 12F).