Systematics, phylogeny and biogeography of the Australasian leaf-curling orb-weaving spiders (Araneae: Araneidae: Zygiellinae), with a comparative analysis of retreat evolution

Abstract

We revise and monograph the Australasian clade of the araneid subfamily Zygiellinae F.O. Pickard-Cambridge. Several members of this clade construct conspicuous leaf retreats at the hub of their webs. We gathered and analyzed a matrix of 95 taxa of zygiellines and close relatives with sequence data from six genetic markers (12S rRNA, 16S rRNA, 18S rRNA, 28S rRNA, cytochrome oxidase c subunit I, and histone H3), in addition to 235 morphological and behavioral characters. Analyses conducted using parsimony, maximum likelihood, and Bayesian methods indicate that Phonognatha Simon is paraphyletic as currently circumscribed, which we accommodate by erecting the genus Artifex gen. nov. Our analyses support Zygiellinae as the earliest diverging araneid subfamily. Biogeographic analyses using BioGeoBEARS support multiple colonizations of zygiellines to New Caledonia from Australia, congruent with the island's geology. Furthermore, analysis of the retreat types show using leaf retreats integrated with the hub to have arisen at least three times independently. We describe one new species, Phonognatha tanyodon sp. nov., redescribe three species of Phonognatha, three species of Deliochus Simon, and two species of Artifex gen. nov. Three species of Araneus Clerck and Phonognatha are synonymized with these taxa, and four species are misplaced in Zygiellinae.