Phil R. Bell

University of New England (Australia) | UNE · School of Environmental and Rural Science

Megaraptoridae comprises a clade of enigmatic Gondwanan theropods with characteristic hypertrophied claws on the first and second manual digits. The majority of megaraptorids are known from South America, although a single genus (Australovenator) plus additional indeterminate material is also known from Australia. This clade has a controversial pla...

Among living vertebrates, soft tissues are responsible for labile appendages (combs, wattles, proboscides) that are critical for activities ranging from locomotion to sexual display [1]. However, soft tissues rarely fossilize, and such soft-tissue appendages are unknown for many extinct taxa, including dinosaurs. Here we report a remarkable "mummif...

Ankylosaurian dinosaurs are most notable for their abundant and morphologically diverse osteoderms, which would have given them a spiky appearance in life. Isolated osteoderms are relatively common and provide important information about the structure of the ankylosaur dermis, but fossilized impressions of the soft-tissue epidermis of ankylosaurs a...

Bite marks attributable to Tarbosaurus bataar are identified on fragments of gastralia from the giant putative ornithomimosaur, Deinocheirus mirificus. Hundreds of bone fragments collected from the holotype quarry of D. mirificus by members of the Korea-Mongolia International Dinosaur Project at Altan Uul III (Mongolia) were visually inspected for...

Sauropod teeth are commonly categorized taxonomically by two well‐established measurement indices: slenderness index (SI; apicobasal height/mesiodistal width), which quantifies breadth, and compression index (CI; labiolingual width/mesiodistal width), which quantifies cross‐sectional circularity. Although both indices are used to infer high‐level t...

Reported lizard material from the Wapiti Formation (central-western Alberta, Canada) is limited to fragmentary remains of Kleskunsaurus grandeprairiensis and Socognathus unicuspis, a partial dentary attributed to Chamops cf. C. segnis, and a vertebra reportedly comparable to those of the much larger lizard Palaeosaniwa canadensis. P. canadensis is...

Hadrosaurids are the most common dinosaur fossil found in the Campanian-Maastrichtian (79-67 Ma) Wapiti Formation of northwest Alberta. However, beyond Edmontosaurus regalis, it is not yet clear which hadrosaurid species are present in the formation. It is therefore not well understood if and how these northern hadrosaur communities differed in div...

In 2020, the Australasian palaeontological association Australasian Palaeontologists (AAP) joined the Australian government-supported Australian National Species List (auNSL) initiative to compile the first Australian Fossil National Species List (auFNSL) for the region. The goal is to assemble comprehensive systematic data on all vertebrate, inver...

Morphology of keratinised toe pads and foot scales, hinging of foot joints and claw shape and size all inform the grasping ability, cursoriality and feeding mode of living birds. Presented here is morphological evidence from the fossil feet of early theropod flyers. Foot soft tissues and joint articulations are qualitatively assessed using laser-st...

The Frankfurt specimen of the early-branching ceratopsian dinosaur Psittacosaurus is remarkable for the exquisite preservation of squamous (scaly) skin and other soft tissues that cover almost its entire body. New observations under Laser-Stimulated Fluorescence (LSF) reveal the complexity of the squamous skin of Psittacosaurus, including several u...

Background In egg-laying amniotes, the developing embryo is tethered to a number of the extraembryonic membranes including the yolk sac and allantois that deliver oxygen and nutrients and remove metabolic waste products throughout embryonic development. Prior to, or soon after hatching, these membranes detach from the animal leaving a temporary or...

Australian dinosaur research has undergone a renaissance in the last 10 years, with growing knowledge of mid-Cretaceous assemblages revealing an endemic high-paleolatitude Gondwanan fauna. One of its most conspicuous members is ankylosaurs, which are rare but nonetheless occur in most Australian dinosaur-bearing formations spanning the uppermost Ba...

Patterns of Late Cretaceous terrestrial vertebrate diversity across North America have been interpreted primarily in terms of biogeographic provincialism driven by latitude or coastal-inland habitat gradients. A major difficulty in determining the influence of these two gradients is the existence of some large gaps in the terrestrial fossil record,...

Among non-avian dinosaurs, fossilized skin is most comprehensively represented in the hadrosaurids. Here we provide the first full descriptions of hadrosaurid skin from the Late Cretaceous (Maastrichtian) Frenchman Formation in southern Saskatchewan. Based on the geological age and associated skeletal material, the specimen is tentatively identifie...

The Frankfurt specimen of the early-branching ceratopsian dinosaur Psittacosaurus is remarkable for the exquisite preservation of squamous (scaly) skin and other soft tissues that cover almost its entire body. Newly detected details revealed under Laser-Stimulated Fluorescence (LSF) reveals the complexity of the squamous skin of Psittacosaurus , in...

Discovered in 1852, the scaly skin belonging to Haestasaurus becklesii was the first to be described in any non-avian dinosaur. Accordingly, it has played a crucial role in the reconstruction of sauropod integument and dinosaurs more broadly. Here, we reassess this historic specimen using Laser-Stimulated Fluorescence (LSF), revealing extensive, pr...

The Wapiti Formation of northwest Alberta and northeast British Columbia, Canada, preserves an Upper Cretaceous terrestrial vertebrate fauna that is latitudinally situated between those documented further north in Alaska and those from southern Alberta and the contiguous U.S.A. Therefore, the Wapiti Formation is important for identifying broad patt...

Crocodylians are among Earth’s most successful hyper-carnivores, with their crocodyliform ancestors persisting since the Triassic. The diets of extinct crocodyliforms are typically inferred from distinctive bite-marks on fossil bone, which indicate that some species fed on contemporaneous dinosaurs. Nevertheless, the most direct dietary evidence (i...

Modern birds are typified by the presence of feathers, complex evolutionary innovations that were already widespread in the group of theropod dinosaurs (Maniraptoriformes) that include crown Aves. Squamous or scaly reptilian-like skin is, however, considered the plesiomorphic condition for theropods and dinosaurs more broadly. Here, we review the m...

The integument of the theropod dinosaur Carnotaurus sastrei from the Upper Cretaceous of Argentina is here described in detail for the first time. The scaly skin of this abelisaurid is the most completely preserved of any theropod and the only example of this form of integument known outside of Tetanurae (excluding footprints). The skin is preserve...

Hadrosaurid (duck-billed) dinosaur bonebeds are exceedingly prevalent in upper Cretaceous (Campanian–Maastrichtian) strata from the Midwest of North America (especially Alberta, Canada, and Montana, U.S.A) but are less frequently documented from more northern regions. The Wapiti Formation (Campanian–Maastrichtian) of northwestern Alberta is a large...

Fossil tracks should theoretically capture differences in pedal anatomy between growth stages of the same taxon, particularly those related to the soft tissue of the foot, providing a more realistic view of pedal ontogeny than skeletal material alone. However, recognizing these ontogenetic trajectories is complicated by the influence of preservatio...

A new articulated postcranial specimen of an indeterminate ankylosaurid dinosaur from the Upper Cretaceous (middle-upper Campanian) Baruungoyot Formation from Hermiin Tsav, southern Gobi Desert, Mongolia includes twelve dorsal vertebrae, ribs, pectoral girdles, forelimbs, pelvic girdles, hind limbs, and free osteoderms. The new specimen shows that...

Epidermal scales among modern reptiles are morphologically diverse and serve a variety of functions ranging from moisture balance to chemoreception. Despite being predominantly squamous-skinned (scaly), the functional implications of this type of integument have never before been explored for a dinosaur. Re-examination of the holotype of the therop...

Late Cretaceous tracks attributable to deinonychosaurs in North America are rare, with only one occurrence of Menglongipus from Alaska and two possible, but indeterminate, occurrences reported from Mexico. Here we describe the first probable deinonychosaur tracks from Canada: a possible trackway and one isolated track on a single horizon from the U...

The sparse record of Cretaceous crocodyliforms in Australia comprises only three species, all within the genus Isisfordia. Isisfordia duncani Salisbury et al., 2006 is from the Albian-Turonian Winton Formation of Queensland, and both Isisfordia molnari Hart et al., 2019 and Isisfordia selaslophensis Etheridge, 1917 have been described from opalized...

Predominately, occurances of Australian sauropods from the Early to mid‐Cretaceous of Queensland and Western Australia, lie between ~45° and 55°S palaeolatitude. The Cenomanian Griman Creek Formation, which straddles the New South Wales–Queensland border, preserves arguably one of the richest Cretaceous terrestrial faunas in Australia. Although sau...

Our knowledge of the reproductive biology of dinosaurs covers a range of aspects, from brooding behaviour to nesting style and the timing of sexual maturity. Yet, the basic anatomy and function of the cloaca in non-avialan dinosaurs remains unknown. Here, we describe the outer morphology of the only known non-avialan dinosaur cloaca, preserved in a...

Early in amniote evolution, epidermal scales evolved in stem reptiles as an efficient barrier against water loss and ultraviolet radiation, making them a key development in the transition to a fully terrestrial existence [ 1 • Lillywhite H.B. • Maderson P.F.A. Skin structure and permeability. Biol. Reptilia. 1982; 12 : 397-442 • Google Scholar...

The Hawkesbury Sandstone (Hawkesbury Series, Sydney Basin) on the southeastern coast of New South Wales, Australia, preserves a depauperate but important vertebrate tetrapod body-fossil record from the Early and Middle Triassic. As with many fossil sites around the world, the ichnological record has helped to shed light on the paleoecology of this...

The diversity of Australia’s theropod fauna from the ‘mid’-Cretaceous (Albian–Cenomanian) is distinctly biased towards the medium-sized megaraptorids, despite the preponderance of abelisauroids in the younger but latitudinally equivalent Patagonian theropod fauna. Here, we present new evidence for the presence of ceratosaurian, and specifically abe...

The holotype specimen of the megaraptorid Australovenator wintonensis, from the Upper Cretaceous Winton Formation (Rolling Downs Group, Eromanga Basin) of central Queensland, is the most complete non-avian theropod found in Australia to date. In fact, the holotype of A. wintonensis and isolated megaraptorid teeth (possibly referable to Australovena...

Dinosaurs were remarkably climate-tolerant, thriving from equatorial to polar latitudes. High-paleolatitude eggshells and hatchling material from the Northern Hemisphere confirms that hadrosaurid ornithopods reproduced in polar regions. Similar examples are lacking from Gondwanan landmasses. Here we describe two non-iguanodontian ornithopod femora...

Fossil crayfish are typically rare, worldwide. In Australia, the strictly Southern Hemisphere clade Parastacidae, while ubiquitous in modern freshwater systems, is known only from sparse fossil occurrences from the Aptian–Albian of Victoria. We expand this record to the Cenomanian of northern New South Wales, where opalized bio-gastroliths (tempora...

Preserved labile tissues (e.g., skin, muscle) in the fossil record of terrestrial vertebrates are increasingly becoming recognized as an important source of biological and taphonomic information. Here, we combine a variety of synchrotron radiation techniques with scanning electron and optical microscopy to elucidate the structure of 72 million-year...

The Australian Mesozoic crocodyliform record is sparse in comparison to other Gondwanan localities. A single formally-named taxon is known from this interval; Isisfordia duncani (Winton Formation, Albian-Turonian, Queensland). We present a previously undescribed crocodyliform braincase from the Griman Creek Formation (Cenomanian), New South Wales,...

Globally, non-hadrosauroid iguanodontians (‘basal iguanodontians’) reached their acme in terms of diversity during the Early Cretaceous. However, Gondwanan representatives of this clade are rare and are represented in Australia only by the enigmatic Muttaburrasaurus langdoni (upper Albian; Mackunda Formation). Here, we describe a new iguanodontian,...

The Campanian to Maastrichtian Wapiti Formation of northern Alberta preserves a rich vertebrate fauna notably including fish, turtles, champsosaurs, lizards, dinosaurs, and mammals. However, this assemblage remains less thoroughly explored than its roughly coeval equivalents in southern Alberta and the western United States, partly because the fore...

Preserved labile tissues (e.g. skin, muscle) in the fossil record of terrestrial vertebrates are increasingly becoming recognized as an important source of biological and taphonomic information. Here, we combine a variety of synchrotron radiation techniques with scanning electron and optical microscopes to elucidate the structure of 72 million-year...

Preserved labile tissues (e.g. skin, muscle) in the fossil record of terrestrial vertebrates are increasingly becoming recognized as an important source of biological and taphonomic information. Here, we combine a variety of synchrotron radiation techniques with scanning electron and optical microscopes to elucidate the structure of 72 million-year...

The name of the formation in the title was incorrectly spelled. The correct spelling is, 'Griman Creek Formation'.

The limited fossil record of Australian Cretaceous theropods is dominated by megaraptorids, reported from associated and isolated material from the Early Cretaceous of Victoria and the ‘Mid’-Cretaceous of central-north New South Wales and central Queensland. Here, we report on new postcranial theropod material from the early Late Cretaceous Griman...

During the Early Cretaceous, dinosaur communities of the Australian-Antarctic rift system (Eumeralla and Wonthaggi formations) cropping out in Victoria were apparently dominated by a diverse small-bodied 'basal ornithopod' fauna. Further north, in Queensland (Winton and Mackunda formations), poorly-represented small-bodied ornithopods coexisted wit...

Strict consensus of the >100,000 MPTs from the modified Boyd (2015) matrix including Weewarrasaurus.

Complete modified matrix of Madzia et al. (2017).

Reduced strict consensus of the >100,000 MPTs from the modified Boyd (2015) matrix including Weewarrasaurus, following a posterior pruning of 15 unstable taxa.

The mid-Cretaceous Griman Creek Formation (GCF), which crops out near the town of Lightning Ridge in the Surat Basin of north-central New South Wales, Australia, is noteworthy for its opalised vertebrate fauna. The fossil assemblage comprises remains of aspidorhynchid teleosts, lamniform chondrichthyans, dipnoans, chelid and possible meiolaniform t...

Over the past two decades, illegal poaching of vertebrate fossils from the well-known Cretaceous exposures in Mongolia's Gobi Desert has reached epidemic proportions. Following recent efforts led by the Mongolian government to stem the flow of illegal fossils on the black-market, numerous important specimens have now been seized from private collec...

The famous "Dragon's Tomb" Saurolophus bonebed at Altan Uul II preserves multiple complete skeletons with skin impressions, and is exceptional among Nemegt Formation dinosaur localities as the only mass accumulation of articulated individuals. Here, we present results from an on-going paleontological project focused on the Baruungoyot-Nemegt succes...

Bell, P.R., Burns, M.E. & Smith, E.T. XX.XXXX.2017. A probable ankylosaurian (Dinosauria, Thyreophora) from the Early Cretaceous of New South Wales, Australia. Alcheringa XX, xxx–xxx. ISSN 0311-5518. We describe an isolated osteoderm from the Albian Griman Creek Formation where it is exposed near the town of Lightning Ridge in central-northern New...

Recent evidence for feathers in theropods has led to speculations that the largest tyrannosaurids, including Tyrannosaurus rex, were extensively feathered. We describe fossil integument from Tyrannosaurus and other tyrannosaurids (Albertosaurus, Daspletosaurus, Gorgosaurus and Tarbosaurus), confirming that these large-bodied forms possessed scaly,...

The fossil record of Australian pterosaurs is sparse, consisting of only a small number of isolated and fragmentary remains from the Cretaceous of Queensland, Western Australia and Victoria. Here, we describe two isolated pterosaur teeth from the Lower Cretaceous (middle Albian) Griman Creek Formation at Lightning Ridge (New South Wales) and identi...

Xiphactinus is the largest teleost fish known from the Late Cretaceous of North America, and has been found across much of the Western Interior Basin. Despite extensive Late Cretaceous marine deposits occurring in Alberta, there has previously been only two possible records of Xiphactinus from the province, neither of which has been diagnosable to...

Megaraptorid theropods were an enigmatic group of medium-sized predatory dinosaurs, infamous for the hypertrophied claw on the first manual digit. Megaraptorid dentition is largely restricted to isolated teeth found in association with skeletal parts; however, the in situ maxillary dentition of Megaraptor was recently described. A newly discovered...

The hypertrophied manual claws and modified manus of megaraptoran theropods represent an unusual morphological adaptation among carnivorous dinosaurs. The skeleton of Australovenator wintonensis from the Cenomanian of Australia is among the most complete of any megaraptorid. It presents the opportunity to examine the range of motion of its forearm...

Dromaeosaurids were rare components of most Late Cretaceous terrestrial ecosystems and are poorly known from high palaeolatitudes. New dromaeosaurid material, including a frontal and associated postcranial elements, is described from a dense monodominant ceratopsid bonebed on Pipestone Creek, near the city of Grande Prairie (Unit 3, Wapiti Formatio...

The nasal region plays a key role in sensory, thermal, and respiratory physiology, but exploring its evolution is hampered by a lack of preservation of soft-tissue structures in extinct vertebrates. As a test case, we investi-gated members of the "bony-headed" ornithischian dinosaur clade Pachyce-phalosauridae (particularly Stegoceras validum) beca...