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Binfield, P., Archer, M., Hand, S.J., Black, K.H., Myers, T.J., Gillespie, A.K. & Arena, D.A., June 2016. A new Miocene carnivorous marsupial, Barinya kutjamarpensis (Dasyuromorphia), from central Australia. Alcheringa 41, xx–xx. ISSN 0311-5518.A new dasyuromorphian, Barinya kutjamarpensis sp. nov., is described on the basis of a partial dentary recovered from the Miocene Wipajiri Formation of northern South Australia. Although about the same size as the only other species of this genus, B. wangala from the Miocene faunal assemblages of the Riversleigh World Heritage Area, northwestern Queensland, it has significant differences in morphology including a very reduced talonid on M4 and proportionately wider molars. Based on the structural differences and the more extensive wear on its teeth, the central Australian species might have consumed harder or more abrasive prey in a more silt-rich environment than its congener, which hunted in the wet early to middle Miocene forests of Riversleigh.Pippa Binfield [p...

Radiometric U–Pb ages are presented for the Riversleigh World Heritage fossil mammal site in northwestern Queensland, Australia. The ages are determined on speleothems which are generally found in intimate or well-documented association with fossil remains and thus can be assumed to record the age of the latter with a high degree of confidence. The new ages encompass the early (18.2–16.5 Ma) and middle Miocene (15.1–13.5 Ma) deposits at Riversleigh in addition to the younger Rackham's Roost Site which returns early Pleistocene ages. Together, these provide a robust chronological framework for the interpretation of Neogene biotic change in Australia that has, until now, relied almost entirely upon biocorrelative techniques. In particular they permit closer investigation of links between other regions/faunas and allow comparison with other records of climatic and environmental change. This is the first documented example of a methodology that has widespread potential application across many continents and throughout much of Earth history.

Lineage zones within nine contemporaneous mammalian lineages represented in the Cenozoic fossil vertebrate record from the Riversleigh World Heritage Area in northern Australia are used to resolve a series of faunal intervals from the Late Oligocene to Late Miocene. The results agree with previous interpretations of Cenozoic biostratigraphy, provide evidence for the presence of time horizons subdividing some of the four previously recognized Riversleigh biochrons A–D and also provide evidence supporting the allocation of a greater number of Riversleigh faunas to intervals within the Riversleigh biochronology than other methods in previous work. This approach demonstrates the biostratigraphical potential of evolutionary lineages.

The middle Miocene cave deposit at AL90 Site in the Riversleigh World Heritage Area of Queensland, Australia, is the largest excavated palaeokarst deposit within the extensive Cenozoic freshwater limestones of the region. Stratigraphic relationships between various lithological components of the cave deposit indicate a dynamic, complex depositional history including dissolution, infill and reworking of cave materials. Euhedral spar, shelf-stone, calcite rafts and desiccation cracks on cave sediments suggest standing water was variably present in the cave environment. The AL90 Local Fauna is moderately diverse comprising at least 20 vertebrate families and 32 species, yet is taphonomically biased towards large marsupial herbivores (families Diprotodontidae, Macropodidae, and Balbaridae) and cave-dwelling hipposiderid bats. Fossil material is generally exceptionally well-preserved with, in many cases, articulated skeletons recovered. The cave entrance appears to have acted as a natural pit-fall trap. The complex (unconformable) depositional structure and lithology, vertebrate taphonomy and faunal composition at AL90 Site are typical of deposits and assemblages formed in the inner environment of the upper vadose zone. In the past, some similar unroofed cave deposits have been interpreted as clastic fluvio-lacustrine sedimentary deposits formed by surface processes. Analysis of characteristic palaeokarst features at AL90 Site has enabled the identification of other less well-preserved, poorly-exposed or relict cave deposits at Riversleigh and has facilitated interpretation of the depositional and palaeoenvironmental history of those deposits. The findings presented here confirm earlier interpretations that specific, highly-fossiliferous early Miocene to early Pliocene fossil deposits at Riversleigh represent relict caves whose roofs and walls are no longer intact.

Phosphatic concretions containing mineralized three-dimensional plant and invertebrate tissues occur in a mid-Cenozoic terrestrial freshwater carbonate deposit at the Riversleigh World Heritage area in northwestern Queensland, Australia. Mineralogical composition and microstructure of the concretions show that this fossil assemblage was preserved by rapid, early diagenetic phosphatization. Preserved material includes tissues typically considered to have a poor potential for phosphatization, such as internal plant structure and arthropod exoskeletal components. Phosphatization may have been mediated by the presence of microbial films. Study of this rich assemblage has the potential to make significant contributions to both the Australian Cenozoic terrestrial invertebrate fossil record and the Cenozoic plant megafossil record of northern Australia.

Current lists of species-level representation in faunas from 80 Cenozoic fossil localities at the Riversleigh World Heritage Area have been compiled by review of recorded occurrences of taxa obtained from both published and unpublished sources. More than 290 species-level taxa are represented, comprising mammals, amphibians, reptiles, birds, fishes, molluscs and crustaceans. The data are presented for the purpose of ongoing palaeoecological and biochronological studies.

Extinct species of Malleodectes gen. nov. from Middle to Late Miocene deposits of the Riversleigh World Heritage Area, northwestern Queensland, Australia are enigmatic, highly specialized, probably snail-eating marsupials. Dentally, they closely resemble a bizarre group of living heterodont, wet forest scincid lizards from Australia ( Cyclodomorphus ) that may well have outcompeted them as snail-eaters when the closed forests of central Australia began to decline. Although there are scincids known from the same Miocene deposits at Riversleigh, these are relatively plesiomorphic, generalized feeders. This appears to be the most striking example known of dental convergence and possible competition between a mammal and a lizard, which in the long run worked out better for the lizards.