The Australian australidelphians form a clade, for which the name Euaustralidelphia ("true Australidelphia") has been proposed (the branching order within this group is yet to be determined).[4] The study also showed that the most basal of all marsupial orders are the other two South American groups (Didelphimorphia and Paucituberculata, with the former probably branching first). This indicates that Australidelphia arose in South America along with the other major divisions of extant marsupials, and likely reached Australia via Antarctica in a single dispersal event after Microbiotheria split off.[3][4]
Phylogeny
Phylogeny of living Australidelphia based on the work of May-Collado, Kilpatrick & Agnarsson 2015[5] with extinct clades from Black et al. 2012[6]
^Black; et al. (2012). "The Rise of Australian Marsupials: A Synopsis of Biostratigraphic, Phylogenetic, Palaeoecologic and Palaeobiogeographic Understanding". Earth and Life. Springer Netherlands. pp. 983–1078. doi:10.1007/978-90-481-3428-1_35. ISBN9789048134274.