Muribacinus gadiyuli,(Thylacinidae: Marsupialia), a very plesiomorphic thylacinid from the Miocene of Riversleigh, northwestern Queensland, and the problem of paraphyly for the Dasyuridae (Marsupialia)

A new genus and species of thylacinid,Muribacinus gadiyuli,is described from Miocene deposits of Riversleigh in northwestern Queensland.Muribacinus gadiyulishares six character states associated with carnassialisation common among thylacinids, but is uniformly less derived for each. The closest affinities of this species lie with another plesiomorphic thylacinid from Riversleigh,Nimbacinus dicksoni.Two previously recognised thylacinid synapomorphies are reconsidered in the light of new evidence. A growing body of molecular and fossil data indicates that the modern dasyurid radiation is a relatively recent phenomenon. Character analysis suggests that no reliable dental synapomorphies define the Dasyuridae at present. It is proposed that a number of plesiomorphic late Oligocene and Miocene taxa previously considered as dasyurids be regarded as Dasyuromorphiaincertae sedispending the identification of shared derived dental characters for the family, or the discovery of more complete material.