The Australian genus of Eurybrachidae Stål, 1862 (Hemiptera, Fulgoromorpha) Olonia Stål, 1862 is redescribed and reviewed. Seven new species are described: O. bourgoini sp. nov. (N Queensland, Chillagoe), O. danielsi sp. nov. (N Queensland, Cape York Peninsula), O. guillaumei sp. nov. (N Queensland), O. hochae sp. nov. (N Queensland, Undara), O. monteithi sp. nov. (Queensland), O. rylandae sp. nov. (N Queensland, Chillagoe) and O. soulierae sp. nov. (Queensland). Platybrachys nobilis (Stål, 1863) is transferred to Olonia and the new combination Olonia nobilis (Stål, 1863) comb. nov., is proposed. Olonia ornata Lallemand, 1928 and O. apicalis (Walker, 1851) are removed from Olonia and transferred to Platybrachys Stål, 1859 and Maeniana Metcalf, 1952, respectively. Hence, the new combinations Platybrachys ornata (Lallemand, 1928) comb. nov. and Maeniana apicalis (Walker, 1851) comb. nov. are proposed. The new genus Stalobrachys gen. nov. is described to accommodate Olonia alboapicata Jacobi, 1928 and the new combination S. alboapicata (Jacobi, 1928) gen. et comb. nov. is proposed. The male genitalia are illustrated and photographs of habitus, a distribution map, biological data and an identification key are provided. The genus Olonia currently contains twelve species and the genus Stalobrachys gen. nov. has one species.