Molecular relationships of the Australian bandicoot genera Isoodon and Perameles (Marsupialia: Peramelina).

Abstract

12S rRNA sequences resolve the two Australian bandicoot genera Perameles and Isoodon as monophyletic clades which diverged from one another in the middle Miocene. Perameles bougainville, the most divergent species of this genus, appears to have split from the P. gunnii + P. nasuta lineage in the late Miocene, whilst subsequent speciation events occurred in the latter half of the Pliocene. Within Isoodon, although there was a clear recognition of an I. macrourus group of taxa, little support could be found for the continued recognition of the Tasmanian I. obesulus and the Barrow Island form of I. auratus as separate subspecies. Major radiations within Isoodon appear to have occurred in the last 3 million years as Australia became more arid.