A genus-level taxonomic review of primitively segmented spiders (Mesothelae, Liphistiidae).

The spider suborder Mesothelae, containing a single extant family Liphistiidae, represents a species-poor and ancient lineage. These are conspicuous spiders that primitively retain a segmented abdomen and appendage-like spinnerets. While their classification history is nearly devoid of phylogenetic hypotheses, we here revise liphistiid genus level taxonomy based on original sampling throughout their Asian range, and on the evidence from a novel molecular phylogeny. By combining morphological and natural history evidence with phylogenetic relationships in the companion paper, we provide strong support for the monophyly of Liphistiidae, and the two subfamilies Liphistiinae and Heptathelinae. While the former only contains Liphistius Schiödte, 1849, a genus distributed in Indonesia (Sumatra), Laos, Malaysia, Myanmar, Thailand, we recognize and diagnose seven heptatheline genera, all but three removed from the synonymy of Heptathela: i) Ganthela Xu & Kuntner, gen. n. with the type species Ganthelayundingensis Xu, sp. n. is known from Fujian and Jiangxi, China; ii) a rediagnosed Heptathela Kishida, 1923 is confined to the Japanese islands (Kyushu and Okinawa); iii) Qiongthela Xu & Kuntner, gen. n. with the type species Qiongthelabaishensis Xu, sp. n. is distributed disjunctly in Hainan, China and Vietnam; iv) Ryuthela Haupt, 1983 is confined to the Ryukyu archipelago (Japan); v) Sinothela Haupt, 2003 inhabits Chinese areas north of Yangtze; vi) Songthela Ono, 2000 inhabits southwest China and northern Vietnam; and vii) Vinathela Ono, 2000 (Abcathela Ono, 2000, syn. n.; Nanthela Haupt, 2003, syn. n.) is known from southeast China and Vietnam.