Karen Black

Whollydooleya tomnpatrichorum gen. et sp. nov. is a new, highly specialised hypercarnivorous dasyuromorphian from a new mid-Cenozoic limestone deposit southwest of the Riversleigh World Heritage Area in northwestern Queensland. Dental dimensions suggest it may have weighed at least twice as much as the living Tasmanian devil (Sarcophilus harrisii). Although known only from a lower molar, it exhibits a plethora of carnivorous adaptations including a hypertrophied protoconid, tiny metaconid and a battery of vertical carnassial blades between most of the major cusps, most of which incorporate carnassial notches to immobilise materials being sheared. It is unique among dasyuromorphians in having a massive entoconid that closes the entire lingual side of the talonid. Comparison with previously known thylacinid and dasyurid hypercarnivores suggests its relationships are closer to dasyurids than thylacinids in the main because of the very large entoconid, a cusp that is relatively small to absent in all known thylacinids but commonly small to large in dasyurids. However, the extent of enlargement of the entoconid suggests that it is not closely related to previously known Cenozoic hypercarnivorous dasyurids in the genera Dasyurus, Glaucodon, Sarcophilus or any of the other previously described Cenozoic dasyurids. Although the early late Miocene Ganbulanyi djadjinguli is only known from an upper molar, the reduced area of its protocone suggests a correspondingly reduced rather than hypertrophied entoconid in its as-yet-unknown lower molars. Reconsideration of the structure of the talonid in species of Sarcophilus even suggests that within that Quaternary lineage, the entoconid may have been entirely lost, with the posteriorly displaced metaconid taking its functional place as an occlusal counterpart for the blades of the protocone. The large size of the new species signals the earliest indication within the dasyurid radiation of a late Cenozoic trend towards gigantism that became evident in many lineages of Australian marsupials. While the age is uncertain, on the basis of associated taxa such as species of Ekaltadeta, it is probably either mid or late Miocene in age. Geological features of the deposit suggest it was formed within a pool in a cave environment that periodically underwent desiccation. Some grains suggest an aeolian as well as an alluvial and pluvial origin for the deposit. This may relate to current understanding about environmental change that took place in the region following the mid Miocene climate oscillation.

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.

A new specimen of the bizarrely specialised Malleodectes mirabilis from middle Miocene deposits in the Riversleigh World Heritage Area provides the first and only information about the molar dentition of this strange group of extinct marsupials. Apart from striking autapomorphies such as the enormous P3, other dental features such as stylar cusp D being larger than B suggest it belongs in the Order Dasyuromorphia. Phylogenetic analysis of 62 craniodental characters places Malleodectes within Dasyuromorphia albeit with weak support and without indication of specific relationships to any of the three established families (Dasyuridae, Myrmecobiidae and Thylacinidae). Accordingly we have allocated Malleodectes to the new family, Malleodectidae. Some features suggest potential links to previously named dasyuromorphians from Riversleigh (e.g., Ganbulanyi) but these are too poorly known to test this possibility. Although the original interpretation of a steeply declining molar row in Malleodectes can be rejected, it continues to seem likely that malleodectids specialised on snails but probably also consumed a wider range of prey items including small vertebrates. Whatever their actual diet, malleodectids appear to have filled a niche in Australia's rainforests that has not been occupied by any other mammal group anywhere in the world from the Miocene onwards. Until recently, all known dasyuromorphians have been comfortably accommodated into one of three families: Dasyuridae, Thylacinidae and Myrmecobiidae, with the interrelationships of these clades the subject of long-standing controversy 1–6. In the main, this reflects modern dasyuromorphian biodiversity because relatively little of the fossil record of the order is known, with none at all for myrmecobiids. Within dasyurids and thylac-inids, dental morphology is more or less similar resulting in arguments about little more than subfamilial distinctions within existing family-level clades. Recent discoveries being made in the Oligo-Miocene deposits of the Riversleigh World Heritage Area in NW Queensland have resulted in publication of a series of anomalous carnivorous taxa that do not fit comfortably within any of the three known dasyuromorphian families. In most cases these have been published as new genera with uncertain familial position. Wroe 7,8 and Godthelp et al. 9 further argued that some fossil dasyuromorphian-like taxa (e.g., the late Oligocene Ankotarinja and Keeuna 10) do not preserve sufficient features (e.g., complete incisor dentitions) to enable them to be placed with confidence in Dasyuromorphia, or even the cohort clade Australidelphia (which includes all living Australian marsupials plus the South American Dromiciops). Godthelp et al. 9 classified Ankotarinja and Keeuna as Marsupialia incertae sedis, together with the early Eocene Djarthia, which has now been shown to be a

The leaf-nosed bats in Hipposideridae and Rhinonycteridae currently have an Old World tropical to subtropical distribution, with a fossil record extending back to the middle Eocene of Europe. The Riversleigh World Heritage fossil site in northwestern Queensland constitutes a particularly rich archive of faunal diversity for Old World leaf-nosed bats, having yielded more than 20 species. We used 2D geometric morphometrics to quantify cranial shape in hipposiderids and rhinonycterids, with the aim of referring unallocated fossil species, particularly from Riversleigh, to each family within a phylogenetic framework, and using a quantitative approach to reconstruct cranial shape for key clades in these Old World radiations. Our sample comprised 21 extant hipposiderids and rhinonycterids, 1 megadermatid and 1 rhinolophid, in which 31 landmarks were placed in lateral and ventral views, and five measurements were taken in dorsal view. The phylogeny used as the framework for this study was based on an analysis of 64 discrete morphological characters from the dentition, cranium and postcranium scored for 42 extant and fossil hipposiderids and rhinonycterids and five outgroup taxa (rhinolophids and megadermatids). The phylogenetic analysis was conducted using maximum parsimony, with relationships among selected extant taxa constrained to match the results of recent comprehensive molecular studies. Our phylogenetic results suggest that the Riversleigh leaf-nosed bats probably do not represent an endemic Australian radiation, with fossil species spread throughout the tree and several with sister-group relationships with non-Australian taxa. Discriminant analyses (DA) conducted separately on each dataset resulted in cross-validated classification success ranging from 61.9% for ventral landmarks to 71.4% for lateral landmarks. Classification of the original grouped cases resulted in success of 81% for each dataset. Of the eight fossil taxa included as unknowns in the DA, six were found to be assigned to the same group as recovered by the phylogenetic analysis. From our results, we assign the Riversleigh Miocene species Archerops annectens, Brachipposideros watsoni, Brevipalatus mcculloughi, Rhinonicteris tedfordi and Xenorhinos halli to Rhinonycteridae, and Riversleigha williamsi and Hipposideros bernardsigei to Hipposideridae. Our results support Pseudorhinolophus bouziguensis, from the early Miocene of Bouzigues in southern France, as belonging to Hipposideridae, and probably Hipposideros. The reconstructed ancestor of hipposiderids was distinguished from that of the rhinonycterids by having a shorter rostrum, and less of a distinction between the rostrum and braincase.

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.

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

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.

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–
13.5Ma) deposits at Riversleigh in addition to the younger Rackham's Roost Sitewhich 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 amethodology that haswidespread potential
application across many continents and throughout much of Earth history.

Exceptionally well-preserved skulls and postcranial elements of a new species of the plesiomorphic stem macropodiform
Balbaroo have been recovered from middle Miocene freshwater limestone deposits in the Riversleigh World Heritage Area
of northwestern Queensland, Australia. This constitutes the richest intraspecific sample for any currently known basal
‘‘kangaroo’’, and, along with additional material referred to Balbaroo fangaroo, provides new insights into structural
variability within the most prolific archaic macropodiform clade – Balbaridae. Qualitative and metric evaluations of
taxonomic boundaries demonstrate that the previously distinct species Nambaroo bullockensis is a junior synonym of B.
camfieldensis. Furthermore, coupled Maximum Parsimony and Bayesian phylogenetic analyses reveal that our new Balbaroo
remains represent the most derived member of the Balbaroo lineage, and are closely related to the middle Miocene B.
camfieldensis, which like most named balbarid species is identifiable only from isolated jaws. The postcranial elements of
Balbaroo concur with earlier finds of the stratigraphically oldest balbarid skeleton, Nambaroo gillespieae, and suggest that
quadrupedal progression was a primary gait mode as opposed to bipedal saltation. All Balbaroo spp. have low-crowned
bilophodont molars, which are typical for browsing herbivores inhabiting the densely forested environments envisaged for
middle Miocene northeastern Australia.

"The middle Miocene cave deposit at AL90 Site in the Riversleigh World Heritage Area of Queensland, Australia, is the largest excavated paleokarst 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 35 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 pitfall 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.
"

"New material of Wakaleo oldfieldi and W. vanderleueri from the Miocene freshwater limestones of the Riversleigh World Heritage Area, northwestern Queensland, is described. This material includes the first known upper dentition of W. oldfieldi and dentaries of both species bearing the previously undescribed and morphologically distinct M3. Previously, the two species were distinguished only by size differences in P3 and the size of
P3 relative to M1. Wakaleo oldfieldi exhibits a more plesiomorphic M3 that retains a well-developed talonid basin in contrast to W. vanderleueri, which has lost this structure. The phyletic succession and geological occurrences of Wakaleo species make this genus an important taxon in biochronological analyses of Australian Cenozoic assemblages. At Riversleigh, W. oldfieldi is found in deposits allocated to Faunal Zone B and Faunal Zone C, which are regarded as early and middle Miocene in age, respectively. The presence of this species in the Kutjamarpu Local Fauna of central
Australia suggests that fauna may be of a similar age. Broader faunal correlations have suggested Faunal Zone C correlates with the middle Miocene Bullock Creek Local Fauna, which contains the more derived W. vanderleueri. Based on stage-of-evolution arguments, W. oldfieldi should occur in older deposits than those yielding W. vanderleueri. The presence of both species of Wakaleo in Faunal Zone C assemblages at Riversleigh suggests that current presumptions about the contemporaneity of the many Faunal Zone C Sites should be examined more rigorously."

We document morphological variation (both geographical and sexual) in the dentition of the extant koala, Phascolarctos
cinereus, in order to facilitate discrimination of species boundaries in extinct phascolarctids. Considerable variation is evident
in dental structures previously used to diagnose several phascolarctid fossil species. Consistent patterns of morphological
variation are not evident between sexes or geographic regions, with variation as great between samples as within them.Metric
variation is evident between the sexes in upper molar dimensions with Victorian (southern) males significantly larger than
Victorian females, although this is not reflected in lower molar dimensions or in the Queensland (northern) sample. Male
koalas from southern populations generally display significantly larger molars than their northern counterparts; however this
trend is not evident in female upper molar dimensions. In both males and females, some, but not all, lower molar dimensions
are larger in southern populations than northern. In light of these results, a systematic revision of species of Litokoala suggests
L. ‘dicktedfordi’ is a junior synonym of L. kutjamarpensis, and the poorly known L. thurmerae is regarded to be a nomen
dubium. Further, we describe a partial cranium of a new species of koala from Early Miocene sediments in the Riversleigh
World Heritage Area, northern Australia. Litokoala dicksmithi sp. nov. is the fifth koala species recorded from the diverse
rainforest assemblages of Riversleigh and the third species referred to the Oligo-Miocene genus Litokoala. Aspects of cranial
morphology, including a shortened robust rostrum and broad, irregular nasal aperture, confirm placement of Litokoala as
sister taxon to the modern genus Phascolarctos. Relatively large orbits and small body size suggest the possibility that L.
dicksmithi was nocturnal, had enhanced visual acuity, and was a more agile arboreal species than the relatively sedentary
extant koala.