Phylogenetic relationships among Australian species of Poa and other subtribe Poinae genera were studied on the basis of plastid trnT–trnL–trnF and nuclear ribosomal ITS and ETS DNA sequence data. Molecular evidence is provided for two new monotypic endemic Australian genera, Sylvipoa and Saxipoa, on the basis of two species formerly included in Poa, P. queenslandica and P. saxicola, respectively. Both new genera resolved in a clade with three subtribe Poinae genera, the Australian genus Hookerochloa, the South American genus Nicoraepoa, and the arctic genus Arctagrostis. Sylvipoa and Nicoraepoa are sister taxa. Saxipoa resolved as sister to these plus Arctagrostis, but also shares DNA sequence characters with Hookerochloa, suggesting a possible hybrid origin. All other Australian Poa species studied resolved in a subclade within the P. subgenus Poa supersection Homalopoa clade, supporting their classification together in an expanded P. section Brizoides. Five New Zealand and one New Guinea species also resolved in this subclade, supporting their membership in this section. We postulate a minimum of two dispersal events into Australia, one for Poa and one for other Poinae genera, and a minimum of three into New Zealand and two into New Guinea for Poa.