Based on a phylogenetic analysis we revised the Chilean tarantula genera Euathlus and Paraphysa. As results of our analyses, within a wider context of South American lineages, Paraphysa is synonymous of Euathlus, and Phrixotrichus is resurrected. Euathlus and Phrixotrichus are sister genera, supported by their shared palpal organ morphology, especially at the ventral position of the distal prolateral inferior keel, also by spermathecal receptacles with a lateral chamber, and tarsal claws without teeth. Both genera are redefined based on cladistic results, and some of their constituent species are transferred. We describe four new species, and for the first time present the spermathecae of Euathlus parvulus comb. nov. All species described for both genera are diagnosed and keyed. Euathlus now includes: Euathlus antai Perafán and Pérez-Miles sp. nov., Euathlus atacama Perafán and Pérez-Miles sp. nov., Euathlus condorito Perafán and Pérez-Miles sp. nov., Euathlus manicata (Simon 1892) comb. nov., Euathlus parvulus (Pocock, 1903) comb. nov. and Euathlus truculentus L. Koch, 1875. Phrixotrichus now comprises: Phrixotrichus jara Perafán and Pérez-Miles sp. nov., Phrixotrichus scrofa (Molina, 1788) comb. nov. and Phrixotrichus vulpinus (Karsch, 1880) comb. nov. Furthermore, Paraphysa riparia Schmidt and Bolle, 2008 is synonymized with Eupalaestrus weijenberghi (Thorell, 1894), Paraphysa pulcherrimaklaasi Schmidt, 1991 is transferred to Maraca Pérez-Miles, 2006 and Paraphysa peruviana Schmidt, 2007 is considered a nomen dubium.
Journal of Natural History (Print: 0022-2933 Online: 1464-5262 )