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Occurrences of young and immature individuals, relatively rare in the fossil record, are important due to the great amount of morphological and evolutionary information they reveal about a lineage's development. Although crocodylomorphs are the most abundant terrestrial vertebrates found in the Bauru Basin, southeastern Brazil, even outnumbering dinosaurian materials, much remains to be understood about their anatomy, ecology, and ontogeny. Egg fragments, nests and nesting sites attributed to Baurusuchus have been previously described, but unfortunately none of these yielded embryonic or hatchling remains. Here, we describe, for the first time, skeletal material of a small notosuchian yearling, recovered from the Adamantina Formation, with osteological features consistent with a baurusuchid affinity. We provide and discuss osteological and histological evidence of its ontogenetic stage, revealing morphological characters distinct from most adult forms, including conspicuous centro-parapophyseal laminae and developed ventral keels. Computerised tomography data also allowed for the identification of incipient ossification and a novel ontogenetic feature in the diminishing volume of the frontal´s internal recesses. Similar materials will increase our understanding of notosuchian ontogeny and diversity, thus requiring growth characters to be integrated into future phylogenies. [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]

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]

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 Adamantina and Marilia formations are considered to be the richest vertebrate-bearing units in the Bauru Group, Upper Cretaceous, Brazil. In contrast, the fossil content from the Uberaba Formation, which only outcrops in Minas Gerais State, is scarce and poorly understood. In this essay the first taxonomically informative titanosaur remains unearthed from this unit are reported. They comprise anterior caudal vertebrae from two different individuals corresponding to a probably basal titanosaur (CPP-360) and a derived titanosaur (CPP-217). Although these remains can be clearly distinguished from other titanosaurs on the basis of their unique association of characteristics like the presence of mildly procoelous centra, lateral pits in the anterior caudal vertebrae, and prezygapophyses with a dorsal protuberance in anterior caudals in CPP-360 and the presence of strongly developed prespinal, spinopostzygapophyseal and centropostzygapophyseal laminae in CPP-217, more complete materials are needed to propose them new names. [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]