Carlos Roberto A. Candeiro, Stephen L. Brusatte, Felipe M. Simbras, Camila Pereira, Andrà L. Sousa-JÃnior, Ramon Cavalcanti, Daniel Carelli, Isa LÃcia M. Resende, Musa Nogueira & Joyce Brenda F. Souza (2018)
New reports of Late Cretaceous reptiles from the Bauru Group of southern GoiÃs State, Brazil.
Journal of South American Earth Sciences (advance online publication)
Highlights
Most of these records from Central Brazil came from Mato Grosso, western SÃo Paulo, and TriÃngulo Mineiro.
Here we describe a fossil reptile assemblage from the Late Cretaceous Bauru Group, of the southern GoiÃs state: podocnemidoid turtles, crocodyliforms, and titanosaurid dinosaurs.
Despite the fragmentary condition of the new fossils, they demonstrate that the local fauna was diverse during the latest Cretaceous, and generally similar to Bauru Group faunas from other parts of Brazil.
Abstract
Over the past few decades, important fossils of dinosaurs, crocodylomorphs, and other latest Cretaceous vertebrates have been recovered from the Bauru Group of Brazil, giving unique insight into how Gondwanan faunas were evolving before the end-Cretaceous asteroid impact. Most of these records, however, come from a few regions, most notably Mato Grosso, western SÃo Paulo, and TriÃngulo Mineiro. Here we describe a fossil reptile assemblage from the Late Cretaceous of the Adamantina and MarÃlia formations (Bauru Group, Paranà Basin) in a region that has gone largely unexplored: southern GoiÃs State. Although these fossils are isolated and largely incomplete, they record a high diversity of vertebrates, including podocnemidoid turtles, crocodyliforms, and titanosaurid dinosaurs. As previous records from this region were limited to a single indeterminate sauropod bone, these new fossils are the first diagnostic members of their groups from southern GoiÃs State. Despite the fragmentary condition of the new fossils, they demonstrate that the local fauna was diverse during the latest Cretaceous, and generally similar to Bauru Group faunas from other parts of Brazil. These fossils lend further support to the hypothesis that a diverse terrestrial fauna, dominated by dinosaurs and crocodylomorphs but also including turtles, was widespread across South America (and possibly Gondwana) during the very end of the Cretaceous Period.
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Stephen F. Poropat, Sarah K. Martin, Anne-Marie P. Tosolini, Barbara E. Wagstaff, Lynne B. Bean, Benjamin P. Kear, Patricia Vickers-Rich & Thomas H. Rich (2018)
Early Cretaceous polar biotas of Victoria, southeastern Australiaâan overview of research to date.
Alcheringa: An Australasian Journal of Palaeontology (advance online publication)
Although Cretaceous fossils (coal excluded) from Victoria, Australia, were first reported in the 1850s, it was not until the 1950s that detailed studies of these fossils were undertaken. Numerous fossil localities have been identified in Victoria since the 1960s, including the Koonwarra Fossil Bed (Strzelecki Group) near Leongatha, the Dinosaur Cove and Eric the Red West sites (Otway Group) at Cape Otway, and the Flat Rocks site (Strzelecki Group) near Cape Paterson. Systematic exploration over the past five decades has resulted in the collection of thousands of fossils representing various plants, invertebrates and vertebrates. Some of the best-preserved and most diverse HauterivianâBarremian floral assemblages in Australia derive from outcrops of the lower Strzelecki Group in the Gippsland Basin. The slightly younger Koonwarra Fossil Bed (Aptian) is a Konservat-LagerstÃtte that also preserves abundant plants, including one of the oldest known flowers. In addition, insects, crustaceans (including the only syncaridans known from Australia between the Triassic and the present), arachnids (including Australiaâs only known opilione), the stratigraphically youngest xiphosurans from Australia, bryozoans, unionoid molluscs and a rich assemblage of actinopterygian fish are known from the Koonwarra Fossil Bed. The oldest knownâand only Mesozoicâfossil feathers from the Australian continent constitute the only evidence for tetrapods at Koonwarra. By contrast, the BarremianâAptian-aged deposits at the Flat Rocks site, and the AptianâAlbian-aged strata at the Dinosaur Cove and Eric the Red West sites, are all dominated by tetrapod fossils, with actinopterygians and dipnoans relatively rare. Small ornithopod (=basal neornithischian) dinosaurs are numerically common, known from four partial skeletons and a multitude of isolated bones. Aquatic meiolaniform turtles constitute another prominent faunal element, represented by numerous isolated bones and articulated carapaces and plastrons. More than 50 specimensâmostly lower jawsâevince a high diversity of mammals, including monotremes, a multituberculate and several enigmatic ausktribosphenids. Relatively minor components of these fossil assemblages are diverse theropods (including birds), rare ankylosaurs and ceratopsians, pterosaurs, non-marine plesiosaurs and a lepidosaur. In the older strata of the upper Strzelecki Group, temnospondyl amphibiansâthe youngest known worldwideâare a conspicuous component of the fauna, whereas crocodylomorphs appear to be present only in up-sequence deposits of the Otway Group. Invertebrates are uncommon, although decapod crustaceans and unionoid bivalves have been described. Collectively, the Early Cretaceous biota of Victoria provides insights into a unique Mesozoic high-latitude palaeoenvironment and elucidates both palaeoclimatic and palaeobiogeographic changes throughout more than 25 million years of geological time.