The Assassin Spiders of the family Archaeidae from southern Australia are revised, with a new genus (Zephyrarchaeagen. n.) and nine new species described from temperate, mesic habitats in southern Victoria, South Australia and south-western Western Australia: Zephyrarchaea austinisp. n., Zephyrarchaea barrettaesp. n., Zephyrarchaea grayisp. n., Zephyrarchaea janineaesp. n., Zephyrarchaea maraesp. n., Zephyrarchaea markisp. n., Zephyrarchaea melindaesp. n., Zephyrarchaea porchisp. n. and Zephyrarchaea vichickmanisp. n. Specimens of the type species, Zephyrarchaea mainae (Platnick, 1991), comb. n., are redescribed from the Albany region of Western Australia, along with the holotype female of Zephyrarchaea robinsi (Harvey, 2002) comb. n. from the Stirling Range National Park. The previously described species Archaea hickmani Butler, 1929 from Victoria is here recognised as a nomen dubium. A key to species and multi-locus molecular phylogeny complement the species-level taxonomy, with maps, habitat photos, natural history information and conservation assessments provided for all species. ; Michael G. Rix, Mark S. Harvey