A new Oligo–Miocene marsupial lion from Australia and revision of the family Thylacoleonidae

Wakaleo schouteni sp. nov., a dog-sized marsupial lion (Thylacoleonidae), is described from late Oligocene to early Miocene sediments of the Riversleigh World Heritage Area, Queensland, Australia. Fossils of this new species include a near-complete cranium, dentaries and postcrania. This species is the second thylacoleonid known from late Oligocene sediments. The other, Priscileo pitikantensis Rauscher, 1987, from the Etadunna Formation of South Australia, is known from teeth, part of a palate and postcrania. Wakaleo schouteni exhibits cranial and dental morphology characteristic of species of Wakaleo but possesses a relatively plesiomorphic upper dental formula (i.e. three premolars and four molars) within Thylacoleonidae that was formerly regarded to be diagnostic for species of the genus Priscileo. The holotype and humerus of P. pitikantensis have been compared with the new Wakaleo material described here and found to demonstrate conspicuous similarities in morphology of the M² and the humerus. In the absence of other generically diagnostic features, Priscileo is here regarded to be a junior synonym of Wakaleo. Smaller size and relatively minor morphological differences in the proximal humerus of W. pitikantensis comb. nov. distinguish it at the specific level from W. schouteni. Phylogenetic analysis of thylacoleonids recovers Wakaleo as a monophyletic clade. Both Wakaleo pitikantensis comb. nov. and W. schouteni are recovered as plesiomorphic sister taxa to other species of the genus. Wakaleo pitikantensis and W. schouteni extend the temporal range for this genus back into the late Oligocene. Body weight for W. schouteni, based on total skull length, is estimated to be ∼23 kg.

http://zoobank.org/urn:lsid:zoobank.org:pub:CA8A8EC8-4F66-4F1E-81DC-240A0C4080BE