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The Borioteiioidea (Polyglyphanodontia) is a group of lizards commonly found in Cretaceous Laurasian deposits and is considered as the sister group of Teiidae. While the Asian record comprises several well-preserved skulls and skeletons, other Laurasian occurrences are generally known from disarticulated skull material and isolated teeth. Additionally, the Gondwanan record is rare, with only one species described so far, Bicuspidon hogreli , from the Ifezouane Formation, Kem Kem Beds of Morocco. Given their wide geographic distribution, several biogeographic hypotheses were suggested to explain the temporal and spatial distribution of borioteiioids. In this study, we report the first record of a borioteiioid from the Lower Cretaceous of South America. The specimen was unearthed from Aptian deposits of the Quiricó Formation (Sanfranciscana Basin), Brazil, and consists of both anterior portions of dentaries. Among other characteristics, the material has transversally wide mid-posterior teeth with two distinct cusps (labial and lingual), as typically seen in species of the genus Bicuspidon. It also exhibits additional features, such first mental foramen facing anteriorly and the remaining ones forming a line in the lateral portion of the dentary, anterior symphyseal process extending from the anterior margin of the symphysis, and symphysis bearing an oval-shaped and thick process. These characteristics allowed us to erect a new species of Borioteiioidea, Cryptobicuspidon pachysymphysealis gen. et sp. nov. Cryptobicuspidon pachysymphysealis is one of the oldest records of Borioteiioidea known so far and suggests that Polyglyphanodontini borioteiioids originated in Gondwana with a posterior dispersal to North America and Europe during the Late Cretaceous. [Display omitted] • A new Polyglyphanodontini lizard is reported from Lower Cretaceous from Brazil. • The Brazilian material seems to be more related to the African occurrences. • These lizards originated in Gondwana and, during Late Cretaceous, reached Laurasia. [ABSTRACT FROM AUTHOR]

In this study we determined total mercury concentrations (THg) in a set of fossils from the Upper Cretaceous Bauru Group, Brazil, and investigated how the incorporation of this element occurs in fossil organisms and in their paleoenvironment. The analyzed fossil specimens were collected from two different locations (Jales and Fernandópolis) of the Adamantina Formation and correspond to samples of teeth, bones, osteoderms, and crocodylomorph eggs (probably laid by Baurusuchidae), and their associated sediments. The samples were submitted to Zeeman atomic absorption spectrometry, showing concentrations ranging from approximately 5 ng.g −1 to 77 ng.g −1 in biomineral matrix. The results show mild fluctuations of Hg concentration in the different types of fossils analyzed, with teeth and bones retrieving more Hg than osteoderms, thus being the most suitable for this type of analysis. Adult specimens of Baurusuchidae showed ∼30% more Hg than juvenile ones in their biomineralized tissues, which points to a continuous process of Hg accumulation throughout the individual's life history. As for the determination of Hg in sedimentary rocks, which has been previously claimed to be an indication of the relationship between volcanic activities and some mass mortality events (MMEs), the analysis of Hg in fossils can furnish additional information for future studies regarding the relationship between disturbances in the Hg cycle triggered by volcanic emissions and MMEs. Additionally, the results also suggest that the concentration of Hg in fossil vertebrates can be used as a tool for discussions about ontogenetic stages and, in some very particular cases, identification of female individuals. [ABSTRACT FROM AUTHOR]

The ichnofabrics and ichnofossils from two outcrops of the Serra da Galga Member (Marília Formation, Upper Cretaceous), in the Municipality of Uberaba, Minas Gerais of Southeastern Brazil, are analyzed: the first is characterized by fluvial deposits (braided rivers) and paleosols with a set of ichnofabrics comprising rhizobioturbation, rhizohalo- Skolithos , Skolithos , Taenidium , and Skolithos - Taenidium barretti ; and the second have more influence of alluvial deposition and is characterized by occurrences of crustacean (decapod) Thalassinoides -like burrows. A reassessment of the Asthenopodichnium marks in the "pseudo-coprolites" is also discussed. The Scoyenia ichnofacies is suggested as being the most representative for the sedimentary deposits of the Serra da Galga Member in Uberaba. [ABSTRACT FROM AUTHOR]

The vertebrate fossil record from the Quiricó Formation, Sanfranciscana Basin (Lower Cretaceous), is scarce, but the remains yet found are of great importance for the understanding of the paleobiogeographic and biogeographic processes that took place during the initial stages that led to the opening of the Atlantic Ocean. In this work, new occurrences of sauropod dinosaur bones and theropod teeth from the Barremian–Aptian Quiricó Formation, collected in Campo Azul and Olhos D'Água, State of Minas Gerais, Brazil, are described. The fossils comprise isolated bones of sauropod dinosaurs, such as fragments of sauropod vertebrae, and isolated theropod teeth, both preserved in lacustrine siltstones and associated sandstones. The anatomical features of the sauropod bones suggest that they can be assigned to Rebbachisauridae and the morphological analysis of the isolated theropod teeth placed them within Abelisauridae and Carcharodontosauridae. This suggests that during the Early Cretaceous, the dinosaurian fauna from the southeastern Brazil was more closely related to African faunas than to other South-American ones. [ABSTRACT FROM AUTHOR]

The Marília Formation (Bauru Group, Upper Cretaceous, Brazil) has furnished a large array of vertebrate fossils. However, its ichnological and botanical contents are poorly explored to date. Here we report findings of invertebrate trace fossils ( Beaconites isp., Skolithos isp., and Taenidium barretti ), rhizoliths associated with rhizomorphs with preserved hyphae, and fossil roots from the Echaporã Member, Marília Formation, São Paulo State, Brazil. The association of trace fossils suggest they can be regarded to the Scoyenia Ichnofacies. The rhizoliths indicate that at least two types of herbaceous/arbustive plants inhabited the area, one of them living in the vadose zone and the other one with roots closer to the water table, under arid/semiarid conditions. Sedimentological analyses suggest the studied outcrop comprises fluvial deposits, with predominance of sand bars that underwent different and relatively long periods of subaerial exposure. [ABSTRACT FROM AUTHOR]

The Cretaceous sedimentary rocks from Uberaba, Minas Gerais, have provided a rich vertebrate fauna unearthed from rocks of the Serra da Galga Member, Marília Formation, Bauru Group, of Maastrichtian age. Together with these fossils, a large number of coprolites have also been found from two main localities, here called the Peirópolis and Serra da Galga sites. During field trips carried out in the last few years, 340 samples have been collected, prepared, and analyzed in laboratory. By using parameters such as weight, density, mineralogical composition, and content, we identified 199 coprolites and 141 inorganic nodules (pseudocoprolites). The coprolites have been divided into four morphotypes, which suggest their producers varied in feeding strategies and size. The taphonomic study, based on morphological characters such as wear, presence of pebbles or pebble marks, and desiccation cracks, suggests they underwent temporal and spatial-mixing, and that the material from the Peirópolis Site were transported essentially by alluvial processes (alluvial fans), whereas the material from the Serra da Galga Site were reworked mainly by fluvial streams. The same taphonomic processes may well have affected other fossils from these sites, which are highly abundant in the rocks of this area. Because of that, this taphonomic aspect becomes an important parameter to be taken into account in future studies on the biota of the region. [ABSTRACT FROM AUTHOR]

Theropod bone remains from the Bauru Group, Upper Cretaceous, Southeastern Brazil, are scarce and poorly preserved. Because of that much of the information about these dinosaurs mainly relies on isolated teeth. Here we report a set of theropod teeth found in association with several crocodylomorph teeth and a well-preserved and semi-articulated sauropod dinosaur from the Adamantina Formation deposits. The teeth were analyzed under both morphological and morphometric point of views and the results showed they correspond to the clades Abelisauridae and Dromaeosauridae. To date, and based on osteological evidence, abelisaurids are the most common theropod clade in Bauru Group deposits. Additionally, although deinonychosaur remains have also been described for this unit, some of the teeth reported here might represent the first evidence of Dromaeosauridae for the Bauru Group. [ABSTRACT FROM AUTHOR]

Abstract: Among titanosaurs, osteoderms are morphologically diverse and have been reported from deposits in South America, Africa, Madagascar, Eurasia and Oceania. In Brazil, titanosaur osteoderms are rare and have only been recorded from Bauru Basin sedimentary rocks. Here, we describe a keeled titanosaur osteoderm, which is the first occurrence of an osteoderm specimen in the São Luís Basin, Northeastern Brazil. This osteoderm is characterized by an external bulb, an internal root, and a very rugose cingulum limiting the external and internal surfaces. These characteristics are typical of Titanosauria dermal bones, and this specimen strengthens the idea that the armored sauropods were present during the early Late Cretaceous of Northeastern Brazil, extending their distribution in the northernmost portion of South America. [Copyright &y& Elsevier]

Notosuchia is a highly diverse group of crocodyliforms that peaked during the Cretaceous period. Their taxonomic abundance and morphological disparity in the Upper Cretaceous Bauru Group (Bauru Basin, Brazil) is remarkable, with over 20 species reported. The stable carbon and oxygen isotope composition of notosuchian bioapatite from two sites (i.e., the Ponto 1 do Price and Fazenda Três Antas) in west Minas Gerais State was analyzed to evaluate differences in feeding habits among the taxa found in both localities. Possible environmental stressors are examined, in parallel to sedimentological, paleopedological, and paleontological studies, which indicate a semi-arid to arid climate for the Bauru Group. Multiple tissues of notosuchian crocodyliforms were included in our study, as well as a testudines carapace fragment, lepisosteiform fish teeth and scales, and host rocks. The mineral textures, X-ray diffraction and stable isotope data support preservation of tooth enamel and scale ganoin bioapatite. The δ13C results point to different feeding habits between two terrestrial, carnivore notosuchians, namely a terrestrial source diet for Uberabasuchus terrificus and an aquatic source diet for Campinasuchus dinizi. The δ18O w for the crocodyliform data was calculated and compared to other Upper Cretaceous sites. Values support dry conditions during the formation of the bioapatite for the Fazenda Três Antas site and point to the Hateg Basin in Romania, yet likely younger, as a good paleoclimatic analogue. [ABSTRACT FROM AUTHOR]

The ichthyofauna of the Lower Cretaceous Quiricó Formation (Sanfranciscana Basin), Minas Gerais, Brazil, comprises so far taxa like Hybodontiformes (Chondrichthyes), Dastilbe , Laeliichthys , Mawsonia , and isolated Amiidae teeth and Semionotiformes scales. Here we report new remains of a dipnoan tooth plate and its associated pterygopalatine and Lepisosteidae material comprising isolated scales, a hyoid arch, and a partially preserved individual including several scales, vertebrae, neural and haemal spines, pterygiophores, and associated anal fin. Although isolated or incomplete, these new fossils, collected from upper sandstone levels of fluvio-lacustrine deposits, increase the diversity of the ichthyofauna of the Quiricó Formation. This discovery adds important information to the understanding of the relationships of Brazilian and African faunas during the initial stages of the opening of the Atlantic Ocean. • New Lepisosteidae and dipnoan fossils from the Cretaceous Quiricó Formation, Brazil. • Increase of Lower Cretaceous Lepisosteidae sites in South America. • Quiricó Formation fauna is similar to coeval North African ones. [ABSTRACT FROM AUTHOR]

The deposits of the Serra da Galga Member, Marília Formation (Bauru Group), in Uberaba, state of Minas Gerais, Brazil, provided a rich fauna of vertebrates of Maastrichtian age. Despite the great faunistic diversity, the plant material recorded so far in these deposits is scarce. Together with the vertebrate remains, a relatively large number of coprolites has been reported for at least two localities in Uberaba, but this material received little attention so far. In this work, we present the first record of palynomorphs found within some coprolites from the Peirópolis and Serra da Galga sites. Monoporate, ephedroid, Gnetaceaepollenites ?, Monosulcites ?, and Podocarpidites pollen types were found. This pollen set shows that the flora was composed of shrubs (probably Gnetophyta), arboreal conifers, and cycads that lived under arid climate conditions. Moreover, saprophytic fungal remains were found within a few coprolites, representing the first record of this kind for the Bauru Group deposits in Minas Gerais. [ABSTRACT FROM AUTHOR]

In this work we describe new remains and possible gastroliths of a sphagesaurid (Mesoeucrocodylia: Notosuchia) unearthed from the Adamantina Formation (Bauru Group, Upper Cretaceous) in the municipality of Fernandópolis-SP, which add new data about the dental, dermal shield, and the post-cranial skeleton morphology of these crocodilians. Phylogenetic analyses place the studied fossil within Sphagesauridae, in a polytomy with Armadillosuchus arrudai and Caryonosuchus pricei. The anatomical comparisons are congruent to the phylogenetic analysis since they also suggest that the specimen herein described is closely related to other larger-bodied Sphagesauridae species, such as Armadillosuchus arrudai. The new skull, appendicular, and dermal elements described in this work may provide data for the elaboration of new phylogenetic characters which can improve cladistic analyses concerning Sphagesauridae species, as well as they may help to better understand the morphological complexity of this family of crocodylomorphs, especially the large-bodied species. [ABSTRACT FROM AUTHOR]