Revision of the Australian planthopper genus Chidaea Emeljanov with a redescription of Cixius sidnicus Stål, 1859 (Hemiptera: Auchenorrhyncha: Fulgoromorpha: Cixiidae)

: As part of the ongoing revision of the Australian Cixiidae, here we revise the endemic genus Chidaea Emeljanov, 2000. Examination of the holotype of Cixius sidnicus Stal, 1859 revealed that it is not congeneric with Cixius nervosus (Linnaeus, 1758) but belongs to the hitherto monotypic genus Chidaea resulting in the new combination Chidaea sidnicus (Stal, 1859). Chidaea dayi Emeljanov, 2000 is redescribed and thirteen new species are described: Chidaea algida sp. nov., Ch. armidalensis sp. nov., Ch. belairensis sp. nov., Ch. bobadeenensis sp. nov., Ch. carinata sp. nov., Ch. crassa sp. nov., Ch. dickinsonorum sp. nov., Ch. etelis sp. nov., Ch. kimbaensis sp. nov., Ch. orangensis sp. nov., Ch. pulyonna sp. nov., Ch. punctata sp. nov., and Ch. wilarra sp. nov. An identification key to species of Chidaea and to Australian genera of Cixiini is presented. Host plant relationships and distribution are discussed. Chidaea is endemic to Australia and occurs in all states and territories apart from the Northern Territory.