Two new genera and three new species of Thylacinidae (Marsupialia) from the Miocene of the Northern Territory, Australia

Three new species and two new genera of Thylacinidae from the Northern Territory of Australia bring the total number of known mid and late Tertiary species to 11 in eight genera. Tyarrpecinus rothi gen. et sp. nov. from the Alcoota Local Fauna (Waite Formation), and Nimbacinus richi sp. nov. and Mutpuracinus archibaldi gen. et sp. nov. from the Bullock Creek Local Fauna (Camfield Beds), are relatively small and amongst the more plesiomorphic members of the family. Phylogeny reconstruction using cladistic methods and biochronological data indicate that a major radiation occurred within the family in pre-Miocene times. Specialisation in the form of dental carnassialisation appears to have evolved in parallel in at least two crown groups, one of which includes the recently extinct ‘Tasmanian wolf’, Thylacinus cynocephalus. The other, together with all the lineages represented by unspecialised species, apparently did not survive into the late Miocene. However, insufficient data are available to show what the regional, let alone continental, pattern of succession was during the Miocene.