Ganguroo robustiter , sp. nov. (Macropodoidea, Marsupialia), a middle to early late Miocene basal macropodid from Riversleigh World Heritage Area, Australia.

ABSTRACT——Cranial and dental remains of the middle to early late Miocene macropodid kangaroo,Ganguroo robustiter, sp. nov., are described. Postcranial remains ofG. robustiterwere previously described as referable toG. bilamina.Ganguroo robustiteris more robust (approximately 20% larger) and more derived thanG. bilaminaandG. bites, in having a larger m4, a well-developed posterolingual ridge and lingual cingulum on P3, a longer P3/p3, and no stylar cusp C on M3–M4. We used previously published data matrices to analyze the phylogenetic relationship ofG. robustiter. Both phylogenetic analyses, using craniodental and postcranial characters, placeG. robustiterwithin Macropodidae, as the sister taxon to sthenurines and macropodines. Species ofGangurooare not found to be monophyletic despite their extreme similarity in character scores. This may be due to the large amount of missing data forG. bilaminaandG. bitesfor which no postcranial remains have been identified. Phylogenetic results are ambiguous, recovering unresolved trees with low bootstrap values, but the generic assignment of these taxa is maintained because they are remarkably similar. Species ofGanguroomay represent a phyletic lineage, with species increasing in size and losing cusp/cuspids on their premolars through time, which appears to coincide with a broader record of changing vegetation and climates through the middle Miocene. http://zoobank.org/urn:lsid:zoobank.org:pub:D0B542BE-C673-4260-8381-8B163A35AC36 SUPPLEMENTAL DATA——Supplemental materials are available for this article for free at www.tandfonline.com/UJVP [ABSTRACT FROM PUBLISHER]