Diversity of Pholcus Spiders (Araneae: Pholcidae) in China’s Lüliang Mountains: An Integrated Morphological and Molecular Approach

SIMPLE SUMMARY: Pholcus is the most diverse spider genus in Pholcidae, and is widely distributed in the Palaearctic, Indo-Malayan, Afrotropical, and Australasian Regions. Previously, the Pholcus spiders have not been recorded from the Lüliang Mountains of North China. We undertook an expedition there for the first time. Phylogenetic analyses of DNA sequence data from four gene fragments (COI, H3, wnt, 28S) suggested that Pholcus from the Lüliang Mountains were grouped into nine well-supported clades. We adopted an integrative approach, including morphology and four methods of molecular species delimitation (ABGD, GMYC, bPTP, and BPP), to investigate species boundaries. Such analyses identified the nine clades as nine separate species, of which eight are new to science. All of them belong to the P. phungiformes species group. ABSTRACT: Spiders of the genus Pholcus were collected for the first time during an expedition to the Lüliang Mountains in Shanxi Province, North China. Phylogenetic analyses of DNA sequence data from COI, H3, wnt, and 28S genes allowed us to group them into nine well-supported clades. We used morphology and four methods of molecular species delimitation, namely Automatic Barcode Gap Discovery (ABGD), the Generalized Mixed Yule Coalescent (GMYC), Bayesian Poisson Tree Processes (bPTP), and Bayesian Phylogenetics and Phylogeography (BPP), to investigate species boundaries. These integrative taxonomic analyses identified the nine clades as nine distinct species, comprising Pholcus luya Peng & Zhang, 2013 and eight other species new to science: Pholcus jiaocheng sp. nov., Pholcus linfen sp. nov., Pholcus lishi sp. nov., Pholcus luliang sp. nov., Pholcus wenshui sp. nov., Pholcus xiangfen sp. nov., Pholcus xuanzhong sp. nov., and Pholcus zhongyang sp. nov. The species occur in geographic proximity and show many morphological similarities. All of them belong to the P. phungiformes species group. The records from the Lüliang Mountains represent the westernmost distribution limit of this species group.