New eremaeozetid mites (Acari: Oribatida: Eremaeozetoidea) from the south-western Pacific region and the taxonomic status of the Eremaeozetidae and Idiozetidae

Four new species of Eremaeozetidae are described from Australia: Eremaeozetes schatzi sp. nov. and E. darwinensis sp. nov. from the Northern Territory; E. malleensis sp. nov. from South Australia, and Rogerzetes samueli sp. nov. from Norfolk Island. Eremaeozetes spathulatus Balogh, 1968 from Papua New Guinea is recombined to Rogerzetes. Eremaeozetes undulatus Mahunka 1985 sensu Aoki 2006 from the Ryukyu Islands is a previously undescribed species. It is differentiated from E. undulatus Mahunka 1985 from St. Lucia and named Eremaeozetes aokii sp. nov. Retrozetes gen. nov. is proposed, containing the type species, R. koghisensis sp. nov., R. mirabilis sp. nov. and R. novaecaledoniae sp. nov. from New Caledonia, as well as R. fernandezi sp. nov. from Papua New Guinea. Eremaeozetes hanswursti Mahunka, 1999 from Singapore is recombined to Retrozetes. A new species of Idiozetes, I. hagenensis sp. nov., is described from Papua New Guinea. Idiozetidae is considered to be a junior synonym of Eremaeozetidae, which is re-defined and contains the genera Eremaeozetes, Idiozetes, Mahunkaia, Retrozetes and Rogerzetes. Seteremaeozetes P. Balogh, 1988 is made a junior subjective synonym of Eremaeozetes. Keys are provided to the genera of Eremaeozetidae and species of Retrozetes. A basic synthesis is presented of the biogeography of the Eremaeozetidae of the south-west Pacific region.