Abstract
The genus Nuncia has long been the most speciose within the Opiliones family Triaenonychidae, comprising 63 species and subspecies distributed across New Zealand and South America. Recent molecular studies utilizing Sanger sequencing and ultraconserved elements (UCEs) have indicated that this genus is not monophyletic, and true Nuncia are actually confined to New Zealand. Here, the morphology of all South American triaenonychids is re-examined and DNA sequence data compiled from three markers (18S rRNA, 28S rRNA and cytochrome c oxidase subunit I) for a large number of triaenonychid species, including specimens from all areas with species currently and formerly classified in Nuncia to reassess their phylogenetic position. Based on our findings we 1) revalidate the genus Chilenuncia (Muñoz-Cuevas, 1971) nom. rest.; 2) describe five new genera: Fresiax gen. nov., Mistralia gen. nov., Laftrachia gen. nov., Lautaria gen. nov., Nerudiella gen. nov.; 3) redescribe five species: Fresiaxspinulosa comb. nov., Mistraliaverrucosa comb. nov., Chilenunciachilensis comb. nov., Chilenunciarostrata comb. nov., Nerudiellaamericana comb. nov.; and 4) describe 22 new species of South American triaenonychids: Fresiaxconica sp. nov., Fresiaxfray sp. nov., Fresiaxmauryi sp. nov., Fresiaxpichicuy sp. nov., Mistraliaramirezi sp. nov., Laftrachiarobin sp. nov., Lautariaceachei sp. nov., Nerudiellacachai sp. nov., Nerudiellacaramavida sp. nov., Nerudiellacautin sp. nov., Nerudiellachoapa sp. nov., Nerudiellacuri sp. nov., Nerudiellagoroi sp. nov., Nerudiellajaimei sp. nov., Nerudiellamalleco sp. nov., Nerudiellapenco sp. nov., Nerudiellapichi sp. nov., Nerudiellaportai sp. nov., Nerudiellaquenes sp. nov., Nerudiellavilches sp. nov., Nerudiellawekufe sp. nov., and Nerudiellazapallar sp. nov. Furthermore, we provide detailed illustrations of all the South American species belonging to these lineages formerly classified in Nuncia.