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A taphonomic comparison among ten Quaternary tank deposits bearing megafauna remains in northeastern Brazil allowed the identification of four regional-scale taphonomic aspects controlled by climate seasonality: differential preservation of mega-mammal bones, poor physical integrity, spatial resolution (local) and time averaging (104 years). Sedimentary aspects, such as the high degree of packing of fossiliferous layer, indicate conditions of low clastic detrital sediment input in arid conditions. The correlation among geochronological data of tank deposits and paleoclimatic curves of northeastern Brazil suggest that the climate was arid/semi-arid characterized by seasonality between dry and rainy periods. Thus, we postulate the succession of the two paleoenvironmental and paleoecological scenarios during the late Quaternary affecting the formation of fossiliferous tank deposits: (i) the intensity and duration of arid periods led animals to search for water and food, and consequently, concentration and death near these water sources; and (ii) in the rainy season, carcasses, disarticulated and fragmented bones around these water sources were transported and accumulated through high-energy tractive flows, reworking previously buried skeletal material.

The number of isotopic studies on Quaternary megafauna has increased over the last decades, yet, there is no published data addressing the status of scientific production of this research field. The present study shows the results of a bibliometric research carried out in the Scopus database where the publishing trends within this scientific field was analyzed using the open source software tool SciMAT. We retrieved 278 papers published from 1980 to 2019 and observed that a significant increase in publishing has mainly occurred in the last decade analyzed here. We also identified some of the field´s most influential articles and journals; recognized that carbon, oxygen and nitrogen isotopes are the most used markers in these studies; and that the most cited taxa are representatives of Equidae, Bovidae and Proboscidae. Also, Paleoecology is the basic thematic area, whereas Climate and Paleoenvironmental Changes is the one with the greatest development potential. Our results clearly show that the isotopic study on Quaternary megafauna is still under development and that some subjects could be further explored, such as analyzing more taxa within Carnivora, Pilosa, Notoungulata, Cetartiodactyla and Perissodactyla as well as using other less frequent stable isotope markers, such as strontium, calcium and hydrogen.

We performed a macroscopic and radiological inspection in a set of bones belonging to the fossil mammal assemblage of Zabele Paleontological Site (Late Pleistocene-Northgrippian), in northeastern B...

The recognition of taphonomic alterations is an important step previously to any paleopathological analysis, as some taphonomic features can simulate pathological change on bones. This is a difficult task, but there are some diagnostic criteria that can be used to differentiate them. Here we demonstrate how these features can be macroscopically distinguished using skeletal remains of Quaternary mammals as a model and pointing out how some specific pathological bone changes and diseases can be misinterpreted as taphonomic features (e.g. abrasion marks, corrosion marks, incrustation, post-mortem breakages, and punctures). Although this study has been specifically conducted with Quaternary mammals, the criteria used herein can be employed to any other fossil mammal of equivalent body mass and bone size.

Studies integrating ichnology and paleopedology in paleoenvironmental interpretations are uncommon in Brazilian continental sedimentary successions. Nevertheless, they are crucial for understanding the interactions between sediments, organisms and soil-forming processes. The Albian sediments of the Parnaiba Basin were deposited in continental environments. These are constituted of very fine-to fine-grained sandstones, interbedded with mudstones and composite and compound paleosol profiles with preserved invertebrate and vertebrate trace fossils and rhizoliths. In this study, ichnological, sedimentological and paleopedological data are integrated in order to define the paleoenvironmental conditions of the Albian deposits of the Parnaiba Basin. The depositional environment is interpreted as alluvial with floodplain and crevasse splay deposition. In the paleosol profiles five invertebrate ichnogenera, one vertebrate ichnogenus and two types of rhizoliths were recognized and attributed to Scoyenia ichnofacies. The water saturation level of paleosols evidenced by the distribution of redoximorphic features and the variation of ichnofossil types suggests that the profiles were developed under moderately well drained conditions with short periods of water retention and that the paleoclimate was seasonal and characterized by alternating wet and dry seasons. The alluvial paleoenvironment was characterized by periods of landscape stability in which the pedogenesis exceeded the sedimentation rates and resulted in formation of soil profiles.

A new basal notoungulate, Nanolophodon tutuca gen. et sp. nov., is described. This is represented by maxillary and dental fragments and by isolated teeth. The holotype and referred material were found at the “1968 Fissure” of the Itaborai Basin, Rio de Janeiro State, Brazil. This basin has been regarded as early Eocene in recent contributions. The generalized appearance and brachydonty of the studied specimens, together with the presence of certain typical traits (poorly developed entolophid, well-developed metacone column, etc.) indicate that N. tutuca can be considered among the group of genera traditionally known as henricosborniids, easily distinguishable from Typotheria by the absence of crista 1 and from Toxodontia by the absence of crista intermedia. It is also different from all other henricosborniids by a combination of characters, such as the presence of a long crochet, the development of two small cristae in the ectoloph, and the large paraconid, among others. In the context of a phylogenetic analysis performed, we do not find conclusive evidence about the synonymy between Itaboraitherium atavum and Othnielmarshia pristina. In turn, we question the reference of these forms as henricosborniids, based on the complex occlusal dental pattern observed in both cases. Finally, based on the observations made in the present study, we discuss the identification of the paraconid in notoungulates, which may be associated with some cusps located mesially to the metaconid and identified as pseudoparaconids in past studies.

Urban geotourism itineraries have increased in recent years, since a large number of people are living in major cities and the building stones of the historical and architectural monuments can be used for scientific dissemination. These routes also include information such as geology, palaeontology, architecture, history, tourism and environment. This work presents geoscientific information through a multidisciplinary approach, with emphasis on the fossil content in the building stones. The cultural spaces in the historical centre of Rio de Janeiro City studied are (1) Real Gabinete Portugues de Leitura, (2) Guitarra de Prata store, (3) Confeitaria Colombo, (4) Paco Imperial and (5) Centro Cultural Banco do Brasil (CCBB). This choice was based mainly on the presence of fossiliferous stones, the historical and cultural importance of this heritage and the easy access to the public. The fossils were found in Lioz limestone [Rudistas (Radiolites and Caprinula) (Sites 1, 3, 4 and 5), Gastropods (Sogdianella, Turritella, Pchelinsevia and Neoptyxis) and the ichnogenus Thalassinoides (Site 4)], in the Rosso Ammonitico limestone [Ammonoid Hildoceras and a small undetermined gastropod (site 2)] and in the stromatolitic metalimestone (Site 3). Both Lioz limestone and Rosso Ammonitico are originated from Portugal and Italy, respectively, so the only Brazilian fossil content recorded here is the stromatolites in metalimestone used in CCBB. The dissemination of geodiversity, especially the fossil content, present in these spaces can promote the geoscientific education and the urban geotourism with paleontological approach, attracting a wide public.

The discovery and study of bonebeds can provide unique information on the biology of extinct animals. Here we interpret the taphonomic history of a monotypic bonebed composed by several individuals...

The continental colonization process by plants is an underexplored theme in Brazil, especially concerning taphonomic studies of plants that existed during this age. This study aims to interpret the taphonomic and paleoenvironmental settings that best represent the fossil plant assemblages preserved in the upper strata of the Furnas Formation (Lower Devonian of Parana Basin), at Jackson de Figueiredo county, municipality of Jaguariaiva (Parana), clarifying the potential of these fossil plant assemblages for paleogeographic reconstructions. Taphonomic and sedimentological signatures were analyzed and submitted to multivariate statistical analyses (cluster and correspondence analyses). Two taphonomic groups were identified (Taphofacies A and B). The interpretation of the two groups allowed the visualization of: Taphofacies A, which consists of samples with a dispersed degree of packing, fragmented plant fossils, 40% mica with sizes between 0.5 and 1 mm and no trace fossils, is representative of relatively high-energy conditions; and Taphofacies B, which consists of densely packed plants with partial degree of fragmentation, 10% mica with sizes under 0.5 mm and both horizontal and vertical trace fossils, is representative of relatively low-energy conditions. Our taphonomic data are consistent with previous facies interpretations of a lagoon/interdistributary bay environment. In this context, taphofacies A represents episodic sedimentation events influenced by fluvial dynamics, yielding assemblages that are not suitable for paleogeographic interpretations, while Taphofacies B represents fossil assemblages originated in a low-energy sedimentary regime, with utility for paleogeographic reconstructions.

Although the extinct Quaternary megafauna is widely recorded in northeastern Brazil, geochronological studies carried out on its fossiliferous deposits are still scarce. In this study, Electron Spin Resonance (ESR) was applied to date 12 tooth fragments of Toxodon platensis (Mammalia, Notoungulata) collected in the tank deposit of Lago do Rumo, Baixa Grande, state of Bahia, Brazil. The results obtained in the geochronological analysis performed here reveal ages from around 60 ka to 34 ka for T. platensis in Lagoa do Rumo; and, considering the integration data in the paleontological literature, our results evidence the largest time-averaging ever recorded for tank deposits: around 51 thousand years.

The Late Cretaceous Marilia Formation (Bauru Group, Bauru Basin) is a geological unit that occurs on Sao Paulo, Minas Gerais, Goias, and Mato Grosso do Sul states, Brazil. This formation consists predominantly of paleosols developed in a semiarid/arid environment and recent reappraisal of its formerly known members reduced its lithological composition and geographical distribution. Hence, the Marilia Formation has a very sparse vertebrate fossil record without named species so far. In this contribution we describe a new abelisaurid theropod (Dinosauria) from this unit, namely Kurupi itaata gen. et sp. nov., discovery in the Municipality of Monte Alto, western Sao Paulo State. The holotype MPMA 27-0001/02 consists of three caudal vertebrae and the partial pelvic girdle. Kurupi itaata gen. et sp. nov. shares with other South American abelisaurids fused ischia and caudal vertebrae with long and laterodorsally oriented transverse processes, with fan-shaped distal ends. Autapomorphies of the new theropod include the variation of ∼15° of the inclination of the transverse process between the first (C1) and seventh (C7) caudal vertebra; C1 with anterolaterally projected triangular process placed below the proximodistal mid-portion of the transverse process, and a notch at the anterodistal portion of the transverse process, between a shelf-like process and the anterodistal corner of the transverse process; and anterior caudal vertebrae (present in C1 and C7, inferred in the others) with a cuneiform process, anterodorsally projected, located on the dorsal surface of the transverse process. Phylogenetic analysis recovered Kurupi itaata gen. et sp. nov. among abelisaurid theropods, but was nested in an unresolved massive polytomy of the entire clade. Taphonomic traits on the studied specimens corroborate previous proposals for the paleoenvironmental context of the Marilia Formation. Kurupi itaata gen. et sp. nov. was about 5 m long, with a rigid tail, and cursorial locomotion as indicated by its a muscles attachment and bones anatomy. This new taxon contributes to the knowledge of the Maastrichtian continental fauna of Brazil and increases the diversity of medium-sized abelisaurids in western Gondwana.

We conducted a paleopathological study in 230 fossil specimens that were collected and prepared by Ney Vidal (renowned Brazilian paleontologist) during the 1940s and 50s. These fossils were housed at the Collection of Vertebrate Paleontology of Museu Nacional of the Universidade Federal do Rio de Janeiro (MN/UFRJ), which were tragically lost in the fire that destroyed the Museu Nacional on September 2nd, 2018. Four isolated specimens assigned to Eremotherium laurillardi exhibited pathological alterations (1.9%), diagnosed as spondyloarthropathy (inflammatory arthritis) and linear defect (a type of vertebral endplate defect). Spondyloarthropathy has been often diagnosed in Late Pleistocene glyptodonts and giant ground sloths, but this is the first report of linear defect for any species of Xenarthra.

During the Pleistocene, a diverse fauna composed of large and mega mammals lived in the Northeastern of Brazil, and is generally associated with open environments. We present in this study carbon and oxygen isotopic data of Notiomastodon platensis and Toxodontinae from the fossiliferous deposit of Lajedao do Patricio, Joao Dourado, Bahia, Brazil. The analyzes of δ13C and δ18O were carried out to better understand the paleoecology of these taxa and, consequently, make it possible to obtain paleoclimatic and paleoenvironmental inferences about the region of Lajedao do Patricio fossiliferous deposit. The δ13C values identified for Notiomastodon platensis (−5.67‰ and −6.95‰) and Toxodontinae (−5.62‰ and −7.03‰) indicate a mixed diet for these taxa due to the consumption of C3 and C4 plants, indicating an environmental scenario of vegetation mosaic of dry forest (caatinga) and cerrado during the Pleistocene/Holocene. The comparison between the δ13C data from the megafauna in Northeast Brazil allowed the identification of opportunistic behaviors for Notiomastodon platensis and Toxodontinae, varying between the browser, mixed and grazing habits, according to the characteristics of the habitat in which they lived. The δ18O data and its variations suggest changes in the precipitation regime during the Pleistocene/Holocene transition in the region of the analyzed fossiliferous deposit.

We performed a macroscopic study on six species of Pleistocene sloths from the Brazilian Intertropical Region (BIR) including Valgipes bucklandi, Catonyx cuvieri, Mylodonopsis ibseni, Glossotherium...

As grutas da Provincia Espeleologica Bambui, em Aurora do Tocantins, norte do Brasil, tem revelado importantes acumulacoes fossiliferas atribuidas ao intervalo Pleistoceno Superior–Holoceno. Recentemente, os primeiros registros fosseis da Gruta Tacho de Ouro foram recuperados, sendo estes atribuidos aos taxons Tayassu pecari, Cervidae indet., Odocoileus virginianus, Mazama sp., Palaeolama major, Tapirus sp., Coendou sp. e Catonyx cuvieri. A presenca de taxons extintos entre os achados sugere que a tafocenose pode ser atribuida ao intervalo Neopleistoceno–Holoceno. Informacoes quanto aos habitats reconhecidos para os taxons encontrados na caverna indicam um ambiente afetado por variacoes climaticas neste intervalo, corroborando com a hipotese da nao contemporaneidade dos especimes. A ocorrencia de O. virginianus na Gruta Tacho de Ouro representa o registro mais meridional para a especie no Brasil. A analise tafonomica indica que os animais provavelmente pereceram externamente a gruta, em um clima arido e, posteriormente, foram carreados para o interior da caverna por um fluxo hidraulico de baixa energia, onde foram rapidamente soterrados entrando em contato com o nivel vadoso da gruta. A analise quanto aos vestigios de alimentacao (Fodinichnia) observados nos fosseis apontou que tais danos estao associados a predacao ou necrofagia realizada por carnivoros. Palavras-chave: Provincia Espeleologica Bambui, Aurora do Tocantins, Intervalo Pleistoceno–Holoceno. DOI: http://dx.doi.org/10.4072/rbp.2017.2.05

Tank deposits are an exceptional type of fossiliferous deposit and bear a remarkably fossil record of the Pleistocene megafauna of South America, particularly of Brazil. The taphonomy of vertebrate remains preserved in this type of environmental context was clearly driven by climate, similarly to most of the Quaternary continental fossil record. The formation of the vertebrates fossil record in tank deposits was influenced by the climate seasonality typical of arid climate. The taphonomic history of most tank deposits is a consequence of this seasonality and, as a result, the paleoecological data preserved in their fossil assemblages is reliable with respect to paleobiological and paleoenvironmental settings of the Quaternary ecosystems of the Brazilian Intertropical Region (BIR). Other tank deposits experienced an unusual taphonomic history that, besides climate, was affected by recurrent events of reworking produced by the depositional agents dominant in the surrounding alluvial plains. The conclusions obtained here concerning the main taphonomic settings and formative processes that characterize fossil vertebrate assemblages of tank deposits will help further studies aimed to recover information on the paleoecology of Quaternary fauna collected in such deposits by allowing a better understanding of their time and spatial resolutions and other potential biases.

We performed a paleopathological and paleoepidemiological analysis for a Notiomastodon platensis population (47 individuals) from the Late Pleistocene of Brazil recovered from Quaternary sediments in Aguas de Araxa (QAA), which revealed three different osseous diseases: Schmorl's node, osteomyelitis and osteoarthritis. All diagnosed injuries were observed in adult individuals, with 6.3% of crude prevalence (3/47 individuals) and 10.3% age-specific prevalence (3/29 adults individuals). The lesions suggest a more stress of diseases in adult individuals than in young ones, which can be due to the characteristic of the populational structure (declining population).

Roteiros de observação de aspectos paleontológicos e geológicos nas fachadas e pisos de construções são muito difundidos em vários lugares do mundo e atualmente estão cada vez mais presentes no Brasil. Esse geoturismo urbano permite levar as pessoas para conhecer a geodiversidade sem a necessidade de estar no afloramento in situ. O Museu do Amanhã, localizado na Praça Mauá, nº 1, Centro do Rio de Janeiro, apresenta como revestimento interno e parte do revestimento externo um calcário de coloração que varia de bege a marfim. Esse calcário, proveniente da Formação Jandaíra, Cretáceo Superior da Bacia Potiguar, Nordeste do Brasil, está repleto de fósseis de moluscos gastrópodes. O presente trabalho descreve os fósseis encontrados no piso dentro e ao redor do Museu do Amanhã e propõe um roteiro geoturístico e um folder explicativo. Para elaboração do roteiro foram selecionados oito pontos baseados em quatro aspectos: a) quantidade de fósseis por laje, b) diversidade taxonômica, c) melhor estado de preservação dos fósseis, d) diferentes tipo de fossilização e e) diferenças paleoambientes. Os fósseis identificados no percurso são os seguintes moluscos gastrópodes: Plesioptygmatis Böse, 1906 e Nerinea Deshayes, 1827 (Nerineidae), Tylostoma Sharpe, 1849 (Naticidae), Trochactaeon Meek, 1863 (Trochacteonidae) e Família Fasciolariidae (gênero indeterminado). Como o Museu do Amanhã trabalha exposições relacionadas ao tempo passado, atual e futuro, é possível durante o percurso inserir informações sobre tempo geológico e discutir esse tema de forma mais abrangente. Além disso, esse roteiro, juntamente com o folder explicativo, permitirá os mediadores desenvolverem o conteúdo paleontológico nas visitas guiadas de escolas e público em geral, aproveitando o espaço para diversificar a divulgação científica.

Atualmente, com o auxílio de GPS, outras ferramentas de geoprocessamento e aplicativos, muitos trabalhos científicos sobre paleontologia têm fornecido dados mais precisos sobre os locais de coleta dos fósseis, permitindo a elaboração de mapas digitais. Essas informações são de grande importância, visto que, com a crescente urbanização, muitos afloramentos são destruídos e os dados sobre o local de coleta acabam sendo perdidos. Todavia, esses mapas abrangem apenas uma determinada bacia sedimentar, ou uma unidade litoestratigráfica, ou um determinado sítio fossilífero ou mesmo um pequeno local onde um determinado fóssil foi encontrado. Uma visão da localização exata, ou até mesmo aproximada, de onde esses fósseis foram encontrados em uma região do Brasil só é possível a partir de dados georreferenciados ou de informações geográficas muito precisas. Em função disso, este trabalho, que faz parte de um projeto maior chamado "Mapa digital das principais localidades fossilíferas do Brasil", teve como objetivo a elaboração de um mapa digital dos principais locais de coleta de fósseis da região Sudeste do Brasil. Para isso, foi realizado levantamento bibliográfico dos principais trabalhos científicos e coleções institucionais e criado um banco de dados em forma de planilha, com as ocorrências dos fósseis para serem exibidas em um mapa digital. Esse trabalho permitirá um conhecimento mais preciso dos locais onde são encontrados os fósseis e o mapa e o banco de dados serão disponibilizados tanto para o Departamento Nacional de Produção Mineral (DNPM), auxiliando nas ações de monitoramento, fiscalização e proteção dos sítios fossilíferos, quanto para a comunidade científica e a população como um todo. Além disso, uma visão mais ampla sobre a diversidade paleontológica do Brasil permitirá ações mais específicas de conscientização da população, através de ações educativas nos municípios onde são encontrados os fósseis, no intuito de valorar e preservar os sítios paleontológicos em nível local e regional.

Tooth traces are key evidence in vertebrate taphonomy, paleoecology and paleoichnology. They are product of feeding behavior of vertebrates and can also be evaluated in biostratinomic perspective. Regarding the Quaternary fossil record of vertebrates in Brazil, the taphonomic-paleoecological information of tooth traces has been underexplored. Recently, features of this sort were identified in Quaternary mammals fossils recovered from Lajedo da Escada caves, state of Rio Grande do Norte, northeastern Brazil, consisting in an opportunity to unveil taphonomic, paleoichnological and paleoecological aspects of the Quaternary megafauna. The ichnospecies Machichnus bohemicus and M. fatimae are recorded in the Late Pleistocene-early Holocene age. The latter is a new ichnospecies of Machichnus described herein. The traces M. fatimae and M. bohemicus observed in Glyptotherium sp. were generated outside the cave by an adult individual of the large-sized canid Protocyon troglodytes during event of predation. Nonetheless, M. bohemicus recognized in Eremotherium laurillardi and Smilodon populator was generated by either a juvenile individual of P. troglodytes or an adult of the small-sized canid Cerdocyon thous, in a scavenging context, outside the cave. Probably, other tooth traces previously reported to the Quaternary of Brazil (in the states of Ceara and Minas Gerais) can be assigned to Machichnus.

This work identifies and interprets taphonomic features of the deer fossil assemblage recovered from the Gruta do Urso cave, located in Tocantins State, Northern Brazil. Consequently, its results shed light on the origin of the vertebrate assemblages in cave deposits and paleoecological aspects of Quaternary deer of northern Brazil. The cervid fossil accumulation of the Gruta do Urso cave includes individuals of three species that died outside the cave and, then, underwent disarticulation and weathering during a time span between one and five years. During the necrolysis, they experienced scavenging by large-sized felids and small-sized canids. Then, the disarticulated remains and a mummified hindlimb were transported into the cave by multiple events of low-energy hydraulic flows. Inside the cave, some specimens experienced exposure on the water table and incrustation. The biostratinomic data suggest the taphonomic history of deers around Gruta do Urso cave occurred in arid conditions.

Paleoecological interpretations require detailed taphonomic analyses which can reveal how fossil accumulations are related to the original site of life and death of organisms. In other words, only a taphonomic approach can unveil the quality of a fossil concentration and its potential for paleoecology. A frequent issue in vertebrate taphonomy and paleoecology is the definition of autochthony, parautochthony and allochthony. These terms are widely employed to translate the spatial quality of a fossil assemblage. However, its application in terrestrial vertebrate accumulations, especially in natural tank ones, is quite confused. This work proposes a form of classification of fossil vertebrate accumulations of natural tanks in relation to their proximity to the original place of death of the biocoenoses. The terms “autochthonous”, “parautochthonous” and “allochthonous”, originally defined based on the analysis of marine shelly faunas are reinterpreted in attempt to clarify their application to vertebrate assemblages preserved in natural tank deposits. This classification can also be applied to other trap assemblages, such as fissures, sinkholes and caves.

We applied the ESR (Electron Spin Resonance) dating method to fossils of Notiomastodon platensis (two teeth) and Toxodontinae (two teeth) found in the fossiliferous deposit of Lajedao do Patricio, Joao Dourado, State of Bahia, Brazil, to identify the period of formation of this fossil accumulation. Neutron Activation Analysis was applied to determine the concentrations of the main radioisotopes in enamel, dentine and sediment. The ages found for N. platensis are 16.8 ± 2.6 ka and 12.5 ± 2.3 ka, while the ages for Toxodontinae are 9.6 ± 1 ka and 9.1 ± 1 ka. The results for Notiomastodon. platensis and Toxodontinae are similar to other fossiliferous of Brazil. The estimated maximum time-averaging for Lajedao do Patricio is 11.3 ka, indicating a long period of accumulation of skeletal remains, attributed to resedimentation and reworking. The crossing between the period of formation of fossil assemblage Lajedao do Patricio and ages of climatic variations diponible in paleoclimatic curves produced for the Quaternary of northeastern Brazil indicates different climatic and environmental conditions during the formation of the deposit.

[Resumen] Los tanques (mega gnammas) de origen natural excavados en roca constituyen formas de tamaño medio muy frecuentes en los relieves graníticos del Noreste de Brasil. El estudio de los sedimentos acumulados en el interior de esos tanques naturales se ha convertido en una fuente de datos de gran interés para el conocimiento de la paleontología cuaternaria de Brasil. Este tipo de cavidades habituales en zonas de sustrato granítico, una vez expuestas en superficie han actuado como depocentros locales para los flujos de agua y sus sedimentos asociados, a veces fosilíferos, lo que ha convertido estas concavidades en auténticas tanatocenosis. El estudio sistemático de las acumulaciones fosilíferas se ha convertido así en la principal herramienta para reconstruir las condiciones paleoambientales y paleoecológicas durante parte del período Cuaternario en la Región Intertropical Brasileña. [Abstract] Tanks (mega gnammas) of natural origin excavated in rock constitute medium-sized forms very frequent in the granite reliefs of Northeast Brazil. The study of the accumulated sediments inside these natural tanks has become a source of data of great interest for the knowledge of the quaternary paleontology of Brazil. This type of cavity in areas of granite substrate, once exposed on the surface have acted as local depocenters for water flows and associated sediments, sometimes fossiliferous, which has turned these hollows into true thanatocoenoses. The systematic study of the fossiliferous accumulations has become the main tool to reconstruct the paleoenvironmental and paleoecological conditions during part of the Quaternary period in the Brazilian Intertropical Region

We report the first occurrence of anurans in the Quaternary fossil record of Rio Grande do Norte State. The specimen UERN PV-50 was assigned to the bufonid Rhinella jimi . This finding extends the geographic distribution of this species in the northeastern Brazil during the Late Pleistocene-early Holocene. In paleoenvironmental terms, the occurrence of R. jimi in Riacho Verde paleontological site suggests an arid climate with marked seasonality in that area during the Late Pleistocene-early Holocene and that the paleobiodiversity in that region was higher than the observed in the fossil record. Furthermore, the tanks seem to have been areas of aggregating anurans during raining periods. Finally, based on sedimentological and biostratinomic data, we interpret that Riacho Verde paleontological site preserved a peripheral assemblage. doi: 10.12957/jse.2016.21507

Curimatas Paleontological Site (CPS) preserved one of the most iconic fossil assemblages of Late Pleistocene vertebrates of Brazil. Fossils were collected in a tank deposit,a singular type of Quaternary vertebrate-bearing deposit of South America. In this work, a detailed taphonomic study of the tank assemblage of CPS is presented. This analysis also provides taphonomic and paleoecological data obtained through the application of common multivariate techniques and provides estimates of time- and spatial resolution for tank deposits. The results show that, although the CPS assemblage has experienced an array of taphonomic processes, the long-distance transport was the main process controlling the taphonomic pathway of the thanatocoenosis during the biostratinomic phase, and was responsible for the co-occurrence of other processes, such as abrasion, fragmentation and bioclastic sorting. The origin of the taphonomic modes of vertebrates in the tank deposit of CPS may have been controlled by three major taphonomic phenomena: (i) a taphonomic bias towards the large-bodied size; (ii) long time span of transportation towards the final burial environment; and (iii) some degree of reworking. Furthermore, the analysis of these taphonomic modes supports a previous hypothesis: although taphonomic biases affect the origin of tank assemblages, paleoecological patterns can be preserved with considerable fidelity. The time resolution in tank accumulations is of the order of 10- 3 to 104 years and their spatial resolution seems to be from local to regional.

This study is a taphonomic investigation of a new Late Triassic monotypic association from the Hyperodapedon Assemblage Zone (Santa Maria Formation, southern Brazil). All skeletal elements belong to the traversodontid cynodont Exaeretodon, representing a minimum of four individuals from different ontogenetic stages. Biogenic traces are identifiable on some elements, such as invertebrate scavenging traces, vertebrate bite marks, and evidence of trampling which was probably responsible for accelerating the disarticulation of upper postcanine teeth and for fracturing a skull and a lower jaw. We classify this accumulation as generated by extrinsic biogenic action (predation/necrophagy and possibly trampling) due to the following reasons: (i) random spatial orientation of the elements enclosed into the matrix; (ii) absence of hydraulic equivalence among the specimens and presence of mudstone lenses in close association with the fossils; (iii) presence of nearly all Voorhies’ groups; (iv) association of a large number of cranial elements presenting different stages of disarticulation; and (v) presence of biogenic traces. Both disarticulation patterns and invertebrate scavenging traces indicate that the bones remained exposed for some time before burial. During this time of exposure, carnivore vertebrates also scavenged on some nutritive and transportable postcranial elements. We suggest an ecteniniid cynodont as a potential modifier agent (predation/necrophagy) of this particular monotypic accumulation of synapsids.

Although dinosaurian ichnofaunas are common in the Northeastern Brazilian Interior Basins, osteological remains are poorly represented in these areas. One of the main challenges in vertebrate paleontology in the Lower Cretaceous of this region is to recognize body-fossils, which can unveil the anatomy, functional morphology and paleoecological aspects of the dinosaurian fauna recorded until now only by footprints and trackways. The discovery of a new dinosaur specimen in the Rio Piranhas Formation of the Triunfo Basin opens new perspectives into the comprehension of paleogeographical and temporal distribution of the titanosaur sauropods. Titanosaurs are common in Upper Cretaceous rocks of Brazil and Argentina. The age of the Rio Piranhas Formation is considered to range from Berriasian to early Hauterivian. Thus, the description of this new species opens new viewpoints concerning the paleobiogeographical aspects of these sauropod dinosaurs. Fil: Carvalho, Ismar de Souza. Universidade Federal do Rio de Janeiro; Brasil Fil: Salgado, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; Argentina Fil: Lindoso, Rafael Matos. Instituto Federal de Educação, Ciência e Tecnologia do Maranhão; Brasil Fil: Araújo Júnior, Hermínio Ismael de. Universidade do Estado de Rio do Janeiro; Brasil Fil: Nogueira, Francisco Cézar Costa. Universidade Federal de Campina Grande; Brasil Fil: Soares, José Agnelo. Universidade Federal de Campina Grande; Brasil