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

Abstract

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 Ganthela yundingensis 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 Qiongthela baishensis 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.

From Gondwana to GAARlandia: Evolutionary history and biogeography of ogre‐faced spiders (Deinopis)

“…Furthermore, within multiple islands, we find genetically unique clades that are separated by barriers such as mountain ranges (Figure 3). Similar patterns of high interspecific genetic divergence have been found in dispersallimited lineages of spiders, including Mesothelae (Liphistiidae) spiders as well as mygalomorphs (Hamilton, Formanowicz, & Bond, 2011;Hamilton, Hendrixson, Brewer, & Bond, 2014;Xu, Liu, Chen, Ono, et al, 2015;Xu, Liu, Cheng, et al, 2015;Xu et al, 2016). These finding provides an additional context in which to explore the origin and age of Caribbean taxa, including the potential impact of geology on phylogeny.…”

Extant primitively segmented spiders have recently diversified from an ancient lineage

“…All phylogenetic analyses support the monophyly of Liphistiidae and of eight genera. As the fossil evidence supports a Carboniferous Euramerican origin of Mesothelae, our dating analyses postulate a long eastward over-land dispersal towards the Asian origin of Liphistiidae during the Palaeogene (39)(40)(41)(42)(43)(44)(45)(46)(47)(48)(49)(50)(51)(52)(53)(54)(55)(56)(57)(58). Contrary to expectations, diversification within extant liphistiid genera is relatively recent, in the Neogene and Late Palaeogene .…”

“…The monophyly of each of the mainland Chinese genera Songthela, Vinathela, Sinothela, and in part, Ganthela is well supported in the phylogeny, and also by the dating analysis and morphological diagnostics [51]. The exception is the suboptimal clade support for Ganthela in the parsimony analyses, and poorly resolved relationships within Songthela in most analyses.…”

Origin of spiders and their spinning organs illuminated by mid-Cretaceous amber fossils

“…It is well known that extant mesothele spiders retain traces of external abdominal segmentation (clearly visible as plate-like tergites) and have multi-segmented spinnerets 20 , but opisthosomal segmentation is only visible dorsally while in Chimerarachne segmentation occurs throughout the opisthosoma ( Fig. 2a, d (Fig.…”