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Although metatherians are known since Early Cretaceous, there is little evidence of bone lesions in this extremely diverse mammalian clade. Here, we report an asymptomatic and benign condition name...

The neck posture and function in sauropods have been widely studied during the last decades. The cartilaginous neutral pose (CNP) method is commonly used in biomechanical reconstructions by positio...

Xenungulates are a peculiar group of bilophodont ungulates, widespread over South America during the Paleocene and early Eocene. Here we describe, illustrate and analyse a new Xenungulata, Rodcania...

Freshwater localities dating from the break-up of western Gondwana are important for a better understanding of the faunal composition and biogeographic patterns of taxa that would become established in both South America and Africa. In the Potiguar Basin, the single locality that represents the Albian-Cenomanian span is the Acu Formation. The paleontological content of Acu Formation began to be discovered in 2005 and, after that, a number of fieldworks conducted recovered numerous fossil remains. The remains include eight fish taxa identified as Tribodus, Bawitius, Lepisosteidae, Vidalamiinae, Pycnodontiformes, Mawsonia c.f. lavocati, Asiatoceratodus c.f. tiguidiensis and Ceratodus. The taxa described here are common to other freshwater localities in Africa and South America, revealing some dating problems related to these localities in the western part of Gondwana.

Catfish fossils are mainly represented by disarticulated material, most of which is dorsal and pectoral spines. Morphological data on dorsal and fin spines are described. These materials, collected from two sites of the Adamantina and Marilia formations, Late Cretaceous, of the Bauru Group, reveal the morphologic diversity of the freshwater siluriform taxa. This fauna represents one of the oldest samples of catfish diversity in South America, shortly posterior to its separation from Africa during the Cretaceous. A comparative analysis of these materials with the pectoral and dorsal spines of fossil and extant taxa demonstrated a mosaic of similarities shared with several catfishes, such as the families Bagridae - dorsal spine of morphotype one, Pimelodidae, Ictaluridae and †Bachmannidae - dorsal spine of morphotypes two and three, and Ictaluridae and †Hypsidoridae - pectoral spines of morphotypes one and two.

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.

In this paper we describe macroscopically two types of bone lesions on a caudal vertebra of an indeterminate titanosaur recovered from the Lower-Upper Cretaceous (Albian-Cenomanian) Acu Formation in the Potiguar Basin, Brazil. The first type of lesion corresponds to cystic lesions on cranial and caudal joint surfaces of the vertebral body, which are identified as subchondral cysts. The second type of lesion corresponds to an irregular bone overgrowth located on longitudinal ligament insertion points. This ossification can be associated with an axial spondyloarthropathy or diffuse idiopathic skeletal hyperostosis (DISH). Bone overgrowth on vertebrae is well documented in the dinosaur fossil record, whereas this is only the second case recorded of subchondral cysts.

Several studies have used isolated crocodyliform and theropod teeth as an important tool for taxonomic identification, as they can often be the only record of some taxa. The objective of this paper is the description and identification of the isolated crocodyliform and theropod teeth in order to clarify which taxa inhabited the western portion of the Potiguar Basin during mid-Cretaceous. The material consists of six tooth crowns from Acu Formation (Albian–Cenomanian), Potiguar Basin, northeastern Brazil. The crowns were identified by a set of qualitative (morphological comparisons and cladistics) and quantitative analyses. UFRJ-DG 659Rd was identified through morphological comparison as a peirosaurid crocodyliform due to its true ziphodont condition, enamel with an irregular texture, and faint lingual fluting. Five of the tooth crowns were identified as abelisaurid theropods based on the results of the cladistic analysis and morphological comparison, with the quantitative analysis supporting this result only for two of the five teeth. This result represents the first report of peirosaurids and abelisaurids in Potiguar Basin, and possibly one of the oldest abelisaurid records in Brazil.

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...

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.

Nothrotherium maquinense, Ahytherium aureum and Australonyx aquae are ground sloths endemic of the late Pleistocene of the Brazilian Intertropical Region for which, as opposed to other xenarthrans such as megatheriid sloths and glyptodonts, no information regarding pathological conditions is available. Herein, we describe, based on an anatomopathological examination, four types of lesions for N. maquinense (spondyloarthropathy, Schmorl's node, vertebral trauma and unspecific infection) and one lesion for A. aureum (osteochondritis dissecans). No lesions were observed in A. aquae. Although several different diseases have been diagnosed, considering the significant number of specimens (2,232) and individuals (41) analyzed, low prevalence marks them all.

Este trabalho reporta novas ocorrencias de mamiferos da Megafauna do Quaternario nos sitios paleontologicos de Campo Alegre (municipio de Taperoa, estado da Paraiba) e Lage Grande (municipio de Alagoinha, estado de Pernambuco), Nordeste do Brasil. Sao registrados os seguintes taxons: Hippidion principale (Perissodactyla, Equidae), Panochthus sp. (Cingulata, Glyptodontidae) e Gomphotheriidae indet. (Proboscidea) no deposito de tanque de Campo Alegre; e Equus (Amerhippus) neogeus (Perissodactyla, Equidae) no deposito de tanque de Lage Grande. Em termos paleoambientais e paleoclimaticos, a ocorrencia dos taxons aqui reportados sugere um ambiente mais aberto associado a coberturas florestais e um clima relativamente mais umido e quente na regiao de Taperoa, e areas estritamente abertas e cobertas por pastagens e um clima relativamente mais arido em Alagoinha durante o Pleistoceno Final-Holoceno inicial.

Tumors are thought rare in dinosaurs, previously limited in distribution to a single family – hadrosaurs. Here we recognized two different neoplastic lesions, osteoma and hemangioma, in a single caudal vertebra of a titanosaur dinosaur from the Upper Cretaceous of Brazil, diagnosed on the basis of macroscopic, radiological and histological analysis. This is the first occurrence of neoplasia in a non-hadrosaur dinosaur. Therefore, neoplasia is not restricted to hadrosaur dinosaurs, as previously suggested.

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

The theropod record from the Cretaceous of northeastern Brazil is rare and consists mostly of isolated and incomplete remains, with only four species described. Here we describe, identify and evaluate the diversity of theropod materials from the Albian–Cenomanian Acu Formation, Potiguar Basin. The material consists of seven isolated theropod vertebrae and a tooth. We identify the material as belonging to four theropod groups: Spinosauroidea, Carcharodontosauria, Megaraptora, and Maniraptora. One of the significant results is the occurrence of Megaraptora in the Potiguar Basin; based on the general morphology, some of the bones we describe are very similar to those of Aerosteon and Megaraptor. Another unexpected result is the identification and presence of a maniraptoran caudal vertebrae; these dinosaurs are very rare in Brazil, with few fossils previously described. Furthermore, we identify other groups that have already been found in coeval basins of the Northeast region of Brazil and Africa, including Carcharodontosauria and Spinosauroidea. The presence of these theropod groups in the Acu Formation reveals a dinosaur richness in the Potiguar Basin similar to coeval basins in Northern Africa and increases the known diversity of dinosaurs that once thrived in northern South America.

The Rebbachisauridae (Diplodocoidea) comprises small to medium-sized sauropods that diversified at the end of the Early Cretaceous–beginning of the Late Cretaceous in Africa, South America and Europe. The goal of this paper is to review the distribution of fossils assigned to Rebbachisauridae at Early-Late Cretaceous and describe the first occurrence of this group in the Acu Formation, Potiguar Basin, Brazil. The material consists of five isolated caudal vertebrae. The specimens have the combination of some characteristics shared with rebbachisaurid taxa, such as Limaysaurus, Amazonsaurus and Demandasaurus: (i) the anterior and posterior articular facets of the centrum are sub-hexagonal to sub-quadrangular; (ii) they bear a wide base; (iii) the centrum presents an amphicoelic condition; (iv) the centrum lacks pneumatization in both lateral and ventral surfaces; (v) an anterior position of the neural arch is implied by the anteriorly located centroneural suture of the centrum (Salgado et al., 1997; Wilson and Sereno, 1998; Canudo et al., 2018). The rebbachisaurids have been largely used for biogeographical interpretations due to its presence in both Gondwanan and Laurasian continents; the material presented here is a further evidence of this relationship once the specimens show similarities with both European and Argentinean forms. Furthermore, this occurrence enlarges the presence of the group in Brazil and South America, and is important for a better understanding of the faunistic context of the Northeast of South America and its relationship with other Early-Late Cretaceous faunas.

A set of lesions are re-described and new pathological findings in foot bones of Panochthus sp. (Xenarthra, Cingulata) are presented. The material reexamined in fact presents enthesiophytes instead of osteoartrithis, as previously interpreted. Furthermore, Calcium Pyrophosphate Deposition Disease (CPPD) was observed, a lesion absent in previous report. CPPD also was found in another set of foot bones and it was associated with a congenital fusion of two sesamoids. The material studied were collected in two natural tank deposits, one in Paraíba (material reexamined) and other in Rio Grande do Norte (new pathological findings) State.

Abstract: Riostegotherium yanei from the Itaborai Basin, Brazil, is the oldest known Xenarthra. This paper aims to describe the internal morphology of the osteoderms of Riostegotherium yanei from the perspective of histology and micro-CT approaches, expanding the available data on cingulate osteoderm microstructure. Seven osteoderms of R. yanei were used for the internal microstructure description and eight of Dasypus novemcinctus for comparison. The osteoderms of Riostegotherium yanei lacks the diploe-like structure typical of glyptodonts but has a three-layered structure composed of two layers of non-Haversian compact bone enclosing a central layer of primary and secondary osteons. This internal organization is distinct from other Astegotheriini of comparable age, but similar to Dasypus. The 3D reconstruction of Riostegotherium yanei revealed two patterns of internal organization. Pattern 1 of movable osteoderm is composed of large remodeled areas at the base and a more compact bone at the tongue; in Pattern 2 (both movable and buckler), the internal cavities are much smaller, more numerous, and more interconnected to each other. In one buckler osteoderm, the cavities are organized somewhat radially with a compact central region (Pattern 1). Pattern 1 of both movable and buckler osteoderms resemble that of Dasypus.

Little is known about the tooth wear of South American theropod dinosaurs. This paper describes wear facets in Abelisauridae, Carcharodontosauridae and some indeterminate theropods teeth, from the Marília Formation. Four types of wear facets are proposed: vertically-oriented attritional striations; perpendicular attritional surfaces; oval wear facets; and apical grooves. All these worn surfaces were produced by dental occlusion, except the apical grooves, which are produced by the contact between predator teeth and the prey bone during predator–prey interaction. More detailed biomechanical and hardness testing of teeth and bone may further elucidate the pattern of tooth wear in theropods.

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.

New isolated petrosals from the Itaborai beds of Brazil (late Palaeocene or early Eocene) are here described and referred to the early diverging litoptern Miguelsoria parayirunhor, based on phylogenetic, size, and abundance arguments. Both the external and internal anatomy of these specimens were investigated, which for the first time document many details of the auditory region of a Palaeogene litoptern. Our cladistic analysis, which included our new observations, failed to recover a monophyletic Litopterna but did not exclude it. A constrained analysis for the monophyly of this order showed that several features such as a (sub)quadrangular and anteroposteriorly elongated tensor tympani fossa and a large notch in the vicinity of the external opening of the cochlear canaliculus may constitute synapomorphies for Litopterna. The evolution of several other auditory characters amongst Litopterna is discussed and the relative dimensions of the inner ear and surrounding petrosal in the group were also investigated. This allowed detection of negative allometry of the bony labyrinth within the petrosal, which was confirmed by measurements and regression analysis across a larger sample of placental mammals. This scaling effect probably has an important influence on several characters of the bony labyrinth and petrosal, amongst which are the length of the vestibular aqueduct and cochlear canaliculus. It demonstrates that many aspects of the morphological variation of the bony labyrinth need to be thoroughly investigated before being incorporated into phylogenetic analyses. © 2015 The Linnean Society of London

Neste trabalho apresentamos um kit para aulas práticas que possibilitará, aos estudantes do Ensino Fundamental, conhecer mais sobre a Paleontologia e compreender a utilidade dos fósseis para a interpretação dos ambientes pretéritos e para a datação das camadas sedimentares. A quase totalidade das escolas do Ensino Fundamental II não dispõe de material para aulas práticas sobre temas relacionados à Paleontologia. O kit consiste em réplicas de fósseis brasileiros e de uma cartilha com as informações necessárias para o desenvolvimento das atividades práticas. Com esse intuito, foram utilizadas réplicas de fósseis procedentes da Bacia de Itaboraí, no estado do Rio de Janeiro, de idade paleocênica, e um bloco de rochas da Formação Pirabas, nos estados do Maranhão, Piauí e Pará, de idade miocênica. Este material também representa uma forma de divulgar a paleontologia brasileira e desmistificar o uso de fósseis de dinossauro como recurso único no ensino e divulgação da Paleontologia. In this work we present a kit for laboratory classes for Junior High schools students seeking to teach them more about paleontology and the importance and usefulness of fossils to identify past environments and dating of the sedimentary layers. Almost all Junior High schools do not have satisfactory material for laboratory classes on topics related to Paleontology. The kit consists of replicas of Brazilian fossils and a booklet with the necessary information for the practical activities. For this purpose we used replicas of fossils coming from Itaboraí Basin, Rio de Janeiro state, of Paleocene age, and a block of rock from Pirabas Formation, Maranhão, Piauí and Pará States, of Miocene age. This material is also a way to spread the knowledge Brazilian paleontology and demystify the use of dinosaur fossils as the unique source of paleontological teaching and dissemination.

Acknowledging intraspecific variation is an important part of a reliable species diagnoses. For mammalian taxonomy, tooth morphology is an especially important trait and, therefore, the morphological variability of these structures is also greatly significant. Here we describe all dental variation present for Protolipterna ellipsodontoides based on a sample of more than 500 teeth and provide a differential diagnoses distinguishing from its sister taxa. Initially, the sample was carefully observed under stereo microscope in order to indentify variable traits. Further variable features were also highlighted by a geometric morphometric analysis. We conducted statistic tests to make sure all sample belong to the same species and the single identity of the sample was recovered. A great deal of our results show that structures like the parastyle, hypocone, conular cristae and ectoflexus can show different degrees of development for the same species. The tooth outline may also show some variation in shape and proportions. Many of those features are used as characters of phylogenies, however the current results pointed that those traits are inadequate for this sort of study, as they are variable within a single species. Some accessory cusps were also found, but they have very low frequency. These traits, however, does not have a clear phylogenetic sign and should be not be unadvisedly used in any taxonomy or phylogenetic research. doi: 10.5710/AMGH.11.08.2019.3250

The sparassodonts were the main mammalian predators during most of Cenozoic in South America. The lower Eocene Itaborai Basin/Formation includes the second oldest fossil records of this group in South America: Patene and Nemolestes. Patene is by far the most abundant sparassodont from this formation, with more than 30 specimens referable to a single taxon, Patene simpsoni. Some specimens recovered from the Quebrada de Los Colorados Formation (former Lumbrera Formation – middle Eocene) in Northwestern Argentina have been also referred to P. simpsoni. In order to test the affinities of Patene and the taxonomy of the Argentinean specimens, we performed a review of the genus. We concluded that the specimens from Northwestern Argentina show significant differences from the Brazilian specimens: smaller size, paraconid more developed; metaconid, entoconid and hypoconid more reduced. As a result, the specimens from the Quebrada de Los Colorados Formation were assigned to a new species, Patene coloradensis. Our phylogenetic analysis supported previous hypotheses that exclude Patene from the “Hathliacynidae”, as the former was recovered as an earlier divergent lineage. The results also supported the hypothesis that Allqokirus australis and Mayulestes ferox from the Tiupampa Basin (El Molino Formation, lower Paleocene – Tiupampian), Bolivia, are the oldest known representatives of the Sparassodonta. The results also supported the monophyly of the Pucadelphyida with the inclusion of the Jaskhadelphyidae and closely related taxa in addition to the Pucadelphyidae + Sparassodonta. The Late Cretaceous, North American Varalphadon was not recovered in our phylogenetic analysis as a representative of the Sparassodonta.Based on our results, the Sparassodonta should be considered, based on the current fossil record, as a South American endemic lineage. doi: 10.5710/AMGH.06.05.2019.3222

Biological, stratigraphic, and temporal processes act on the origin of fossil concentrations. The influence of these phenomena on fossil vertebrate accumulations from tank deposits recently began to be analyzed in detail. This paper documents taphonomic patterns recognized in the late Pleistocene fossil vertebrate accumulation from a tank deposit of Lage Grande Paleontological Site (LGPS), Pernambuco State, northeastern Brazil. The preservation observed in LGPS differs strongly from the expected for tank accumulations and, given the high quality of preservation and the low rate of time-averaging inferred (indicated by the low degrees of surface bone modifications), it seems reasonable that LGPS accumulation reflects nearly non-biased biocenotic patterns. Under this hypothesis, Eremotherium laurillardi was the most abundant species in the region of Lage Grande during the late Pleistocene, similarly to other areas with tank deposits. Surprisingly, cingulates were rare or absent. Non-mammalian vertebrates and Glossotherium were rare in that area. Taphonomic signatures indicate that the thanatocoenosis of Lage Grande experienced a short time span of subaerial exposure prior to burial and short transport to inside the tanks by debris-flows. Thus, LGPS accumulation can be classified as parautochthonous. Besides the inferred rapid burial of the LGPS assemblage, when compared to other tank accumulations, another feature that may had generated the peculiar taphonomic setting of LGPS accumulation is the uncommon pond-like morphology of this deposit. Morphology of the tanks may be one additional factor responsible for differential preservation of vertebrates in this kind of deposit.

A new small species of Eocaiman is described on the basis of three anterior left mandibular rami and one isolated tooth. The specimens came from the middle-upper Paleocene Itabora ́ı Basin (Rio de Janeiro State, Brazil; Itaboraian South American Land Mammal Age). The new taxon differs from the other two Eocaiman species, such as its small size, likely participation of the splenial in the mandibular symphysis, a reduced angle between the longitudinal axis of the symphysis and the mandibular ramus, and enlarged ninth and tenth dentary teeth (in addition to the large first and fourth dentary teeth). The participation of the splenial in the mandibular symphysis is a unique character among caimanines (with the only possible exception being Tsoabichi greenriverensis). The new taxon provides new information on the taxonomic and anatomical diversity of the genus Eocaiman, a taxon of prime importance to understand the evolutionary origins of caimans given its position as the basalmost member of Caimaninae. Furthermore, the new taxon has a relatively small body size in comparison with other species of Eocaiman, a case paralleled by other Itaboraian reptilian groups (e.g. snakes), suggesting that this ecosystem provides critical data to test the relationship between reptilian body size and climate. Fil: Pinheiro, André E. P.. Universidade Federal do Rio de Janeiro. Departamento de Geologia. Laboratório de Macrofósseis; Brasil Fil: Fortier, Daniel C.. Universidade Federal do Rio Grande do Sul; Brasil. Universidade Federal de Minas Gerais. Intituto de Geociências; Brasil Fil: Pol, Diego. Museo Paleontológico Egidio Feruglio; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Campos, Diógenes A.. Museu de Ciências da Terra. Departamento Nacional de Produção Mineral; Brasil Fil: Bergqvist, Lílian P.. Universidade Federal do Rio de Janeiro. Departamento de Geologia. Laboratório de Macrofósseis; Brasil

Fossiliferous natural tanks are a singular type of sedimentary deposit restricted to northeastern Brazil, which usually preserves a diversified late Pleistocene vertebrate fauna. Their fossil assemblages are taxonomically well known, but their taphonomy is poorly understood. This work presents a detailed taphonomic analysis of a tank deposit from Jirau site (Ceara State, Northeastern Brazil) to improve understanding of the processes that influenced fossil deposition and preservation in natural tanks and to shed light on paleoecological and paleoenvironmental aspects related to the late Pleistocene vertebrate fauna from Northeastern Brazil. Tank deposits from different localities were also compared to figure out potential taphonomic patterns among them. Additionally, comparisons with other Brazilian Pleistocene deposits and other debris-flow deposits bearing vertebrates were undertaken. The study revealed the predominance of the megamammal Eremotherium laurillardi in the deposit, which we attributed to its abundance in late Pleistocene biocoenosis as well as bone resistance. Scarcity of non-mammalian vertebrates is likely related to their paucity in late Pleistocene biocoenosis. Time-averaging was evidenced by the co-occurrence of different weathering, petrographic and color patterns, and may have affected the ontogenetic profile of the accumulation relative to the original biocoenosis. Analyses of weathering stages, tooth and trample marks, indicate wide exposition of the thanatocoenosis before burial. Abrasion and petrographic patterns allow reworking in the assemblage to be inferred. Permineralization and substitution are the fossilization processes observed. Taphonomy indicates that floods deposited clasts and bioclasts in the tank under an arid or semiarid climate in a debris-flow regime. Comparison with other tank deposits revealed several similar taphonomic features and differences related to sedimentology and stratigraphy. Taphonomic similarities suggest rather homogeneous environmental conditions in the northeastern Brazil during the late Pleistocene, as previously suggested by taxonomic studies. Comparison with other Brazilian Pleistocene deposits shows that tanks have more temporal fidelity than caves, coastal and some fluvial deposits. The Jirau vertebrate accumulation was produced by the reworking and transport of skeletal elements accumulated in a nearby thanatocoenosis and is similar to other better known debris-flow hosted vertebrate accumulations.

Two lungfish tooth plates from the Adamantina and Marilia formations, southeastern Brazil, are redescribed. One represents the youngest record of an asiatoceratodontid for Gondwana. This extends the upper temporal range of this family from Cenomanian to Turonian–Santonian. The other represents a new record of ceratodontids for South America. This discovery corroborates previous descriptions of South American fauna, such as the mixture of relict and ancient Gondwana taxa that disappeared by the end of the Cretaceous or the beginning of the Paleogene. The records add to the extant neotropical ichthyofauna, that survived after the South America–Africa separation.

We report new theropod dinosaur material from the Presidente Prudente Formation (Campanian–Maastrichtian), Bauru Group, in southwestern Sao Paulo state. The material comprises a fragment of right maxilla of Carcharodontosauridae, an anterior portion of a left ilium of Abelisauroidea and a proximal portion of a right fibula of a coelurosaurian. Previous theropod records from the Bauru Basin comprise Abelisauridae and Tetanurae and in Sao Paulo state these have been represented by only a right premaxilla of an abelisaurid and isolated abelisaurid and carcharodontosaurid teeth. The new material reported here represents the first theropod remains from the Presidente Prudente Formation, and includes the first abelisauroid and coelurosaurian postcranial remains from the Bauru Basin in Sao Paulo state and the first latest Cretaceous carcharodontosaurid known from non-dental remains anywhere.

The evolution of the human species is a topic of extreme importance reported in the “Parâmetros Curriculares Nacionais do Ensino Médio – PCNEM” (National Curriculum Standards of Secondary Education), although it is not often taught as part of basic education. This work presents the results of an experimental work performed with 31 students of a religious high school of State of Rio de Janeiro. Learning proficiency was assessed by using two-dimensional (2D) and three-dimensional (3D) illustration techniques of hominids skulls and a Pongidae for teaching Human Evolution. The teaching-learning process using these methodologies was more effective with the application of three-dimensional (3D) illustration techniques. The group of students that used 3D illustrations were able to observe similarities and differences between the presented taxonomic models, and formulate hypotheses about their palaeobiology more consistently than the students that used 2D models. Results of this work indicate that the use of three-dimensional techniques (3D) provides an excellent support to teaching-learning process in basic education, captivating and stimulating new interests of students during the educational process.

BRAZILIAN PLEISTOCENE MEGAFAUNAL TAPHONOMY: FLUVIAL TRANSPORT INDEX (FTI) IN BONE REPRESENTATIVITY ANALYSES. In this work FTI is applied in order to obtain more refined conclusions about the transport process involved in taphonomic history of these accumulations. Data of bone representation from Fazenda Nova tank (in Brejo da Madre de Deus Municipality, Pernambuco State), Jirau and Joao Cativo tanks (both in Itapipoca Municipality, Ceara State) and the fluvial deposits of Araras/Taquara (outcrops of the Rio Madeira Formation, Rondonia State) were used in this analysis. Using the Spearman's nonparametric correlation between bone representation and FTI, we observed the quantitatively homogeneous preservation of skeletal elements less and more transportable in Fazenda Nova and Joao Cativo tanks, what would be expected for deposits of natural tanks, which were influenced by non-selective depositional processes. In Jirau and Araras/Taquara assemblages the preservation was of less transportable elements. In markedly fluvial deposits, as Araras/Taquara, was as expected sorting of elements due to transport, whereas sorting observed in Jirau tank may have not been related to transport, but to other biostratinomic and diagenetic factors. Simulation with Voorhies Groups (VG) for the same deposits showed conclusions contrary to those observed by use of the FTI, revealing that the taphonomic inferences about transport based in the use of VG for Pleistocene Megafauna assemblages can be misleading. RESUMO - Neste trabalho o Indice de Transportabilidade Fluvial (Fluvial Transport Index, FTI) e aplicado em analise de representatividade ossea de concentracoes fossiliferas brasileiras de Megafauna pleistocenica visando a obtencao de conclusoes mais refinadas a respeito do processo de transporte envolvido na historia tafonomica dessas acumulacoes. Os dados de representatividade ossea dos tanques de Fazenda Nova (em Brejo da Madre de Deus, Pernambuco), do Jirau e de Joao Cativo (ambos em Itapipoca, Ceara) e dos depositos fluviais de Araras/Taquara (afloramentos da Formacao Rio Madeira, em Rondonia) foram utilizados nesta analise. Utilizando a correlacao nao parametrica de Spearman entre representatividade ossea e FTI, foi observada a preservacao quantitativamente homogenea de elementos esqueletais menos e mais transportaveis em Fazenda Nova e Joao Cativo, o que seria esperado para depositos de tanques naturais, os quais sofreram a influencia de processos deposicionais nao seletivos. Para os depositos do Jirau e de Araras/Taquara foi observada a predominância de elementos menos transportaveis. Em depositos marcadamente fluviais, como os de Araras/Taquara, e esperada a ocorrencia desses elementos devido a selecao causada pelo transporte, porem, a selecao observada para o Jirau pode nao estar relacionada ao transporte, mas a outros fatores bioestratinomicos e diageneticos. Simulacao realizada com a aplicacao dos Grupos de Voorhies (GV) para os mesmos depositos permitiram conclusoes contrarias aquelas observadas atraves da aplicacao do FTI, revelando que as inferencias tafonomicas de transporte, baseada na utilizacao dos GV em estudos de animais da megafauna pleistocenica, podem ser equivocadas.

CARNIVORE/SCAVENGER TEETH MARKS ON PLEISTOCENE MAMMALS FROM THE NORTHEASTERN BRAZIL. In this work, the first occurrence of carnivore/scavenger teeth marks on Pleistocene fossil mammals collected in the Northeastern Brazil is reported. The fossils are from the "Tank of the Jirau", Itapipoca municipality, Ceara State, and are housed in the Museu de Pre-historia de Itapipoca. The observed features, which are assigned to a large- sized canid, correspond to scratches marks mostly perpendicular to the long axis of the bone, occurring mainly in ribs, vertebrae, tibiae and ulnae. Based on the size of the scratches, the geographical distribution and dietary habits of canids from the Late Pleistocene of Brazil, Protocyon troglodytes (Lund) is the most likely producer of the observed features, although this taxon is not represented in the Jirau fossil accumulation.

TAPHONOMY OF THE FOSSIL MAMMALS ASSEMBLAGE OF THE "1968 FISSURE", SAO JOSE DE ITABORAI BASIN, RIO DE JANEIRO STATE, BRAZIL. Significant amount of taxonomic information has been extracted from fossil mammal assemblages of the Sao Jose de Itaborai Basin, located at Rio de Janeiro State, Southeastern Brazil. However, taphonomic analysis, which are important for understanding the formation of these taphocoenosis, are rare and superficial. A limestone fissure excavated in 1968 (here called "1968 Fissure") stands out among the several known fossiliferous concentrations by its abundance of skeletal elements and by the unique brownish color of the specimens, which differentiate them from those collected in other fissures. This study aims to identify and interpret taphonomic features observed in the taphocoenosis "1968 Fissure", which include fractures, abrasion marks, desiccation marks, teeth marks, bone representativeness, and preservational patterns diagnostic for the occurrence and type of transport during the formation of fossiliferous concentration. Based on taphonomic analysis, the mammal taphocoenosis of the "1968 Fissure" is characterized as parautochthonous, being exposed for a short time before being deposited in the fissure after a short transport, possibly triggered by floods. Probably, predators did not influence the formation of the fossil assemblage studied. Only small mammals occur in the fissure due to a possible selection during the bioestratinomic phase. During the fossildiagenetic phase, several fractures were produced in the material due to compression generated by sediment deposition in the fissure. The observed pattern in the skeletal completeness shows the influence of anatomical features of mammals in differential preservation of skeletal remains during the process of fossilization. RESUMO - Quantidade significativa de informacoes taxonomicas tem sido extraida das assembleias fossiliferas de mami- feros da bacia de Sao Jose de Itaborai, situada no Estado do Rio de Janeiro. Porem, analises tafonomicas, importantes para o conhecimento da formacao dessas tafocenoses, sao raras e superficiais. Dentre as varias assembleias fossiliferas desta bacia destaca-se a procedente de uma fenda escavada em 1968 (denominada "Fenda 1968"), pela abundância e pela coloracao marrom dos elementos esqueletais, que os diferencia dos fosseis procedentes das demais fendas. Este estudo tem como objetivo a identificacao e interpretacao de feicoes tafonomicas observadas na tafocenose da "Fenda 1968", as quais incluem fraturas, marcas de desgaste, de dentes e de dessecacao, representatividade ossea, alem de padroes preservacionais diagnos- ticos para a ocorrencia e o tipo de transporte durante a formacao desta concentracao fossilifera. Com base na analise tafonomica, a tafocenose da "Fenda 1968" caracteriza-se como parautoctone, tendo ficado exposta por pouco tempo antes de ser depositada no interior da fenda por um curto transporte, possivelmente desencadeado por enxurradas. Aparentemen- te, animais predadores nao influenciaram na formacao desta assembleia fossilifera. Apenas mamiferos de pequeno porte ocorrem na fenda devido a uma possivel selecao durante a fase bioestratinomica. Durante a fase fossildiagenetica, varias fraturas foram produzidas no material devido a compressao gerada pelo aporte sedimentar na fenda. O padrao de completude esqueletal observado na tafocenose evidencia a influencia das caracteristicas anatomicas dos mamiferos na preservacao diferencial de restos esqueletais durante o processo de fossilizacao.

The three-dimensional computer modeling consists in acquiring of linear measurements or images of an object, through different methodologies, and the subsequent data insertion in software modeling programs. The acquisition of data can be accomplished through manual measurement of the object dimensions or through photogrammetry, with or without calibration base, videogrammetry with laser trace and webcam, white light projection, 3D laser-scanners (hand and table), and tomography. In paleontology 3D modeling may serve as a tool in works involving morphological and biomechanical studies, in the precise calculation of corporal mass, center of mass observation, volume and posture, and in studies of myological and tissue formation. It also enables structural corrections, simulation of living organisms, and it serves as a tool for disseminate scientific works. In this study, several fossil images was captured and tested in distinct 3D modeling methods to evaluate resolution, operating efficiency, and advantages of its application on paleontological studies. Videogrammetry with laser trace and webcam proved to be the most economic methodology, while videogrammetry with white light projection was the most precise and accurate, being specifically helpful on small samples. Some application examples are also presented. Key words: three-dimensional computer modeling, paleontology, mammal bones, scientific education.

The order Litopterna is represented in the São José de Itaboraí basin by four species belonging to the families Protolipternidae (Protolipterna ellipsodontoides, Miguelsoria parayirunhor and Asmithwoodwardia scotti) and Proterotheriidae (Paranisolambda prodromus). Only the deciduous teeth of P. prodromus are known so far. Isolated milk premolars are described for P. ellipsodontoides and M. parayirunhor. The known specimens assigned to P. prodromus are redescribed. No milk teeth are known for A. scotti. The upper and lower milk teeth of Protolipternidae, especially dP3, are more molarized than their successors, resembling, in several features later Proterotheriidae. They provide new support for the placement of this family within the order Litopterna. The analysis of the wear level of dp2-4/dP2-4 and X-ray images of the lower jaw of P. prodromus suggests that the second teeth of the premolar series, in upper and lower jaw, are retained milk premolars. Some information on tooth replacement pattern of P. ellipsodontoides and P. prodromus are also provided.

The Crocodyliformes are the most represented vertebrate clade in the Upper Cretaceous sequences of the Bauru Group, Paraná Basin. However, some of the species described have an uncertain taxonomic status and phylogenetic position. For instance, "Goniopholis" paulistanus has been assigned as a nomem dubium, due to its description being based on scarce material. The "G". paulistanus specimens (i.e. teeth and a left tibia) were discovered in two different localities in São Paulo state: Mirandópolis and Valparaíso municipalities; where the upper interval of the Adamantina Formation (Early Maastrichtian of Bauru Group) crops out. Revisiting these specimens, we observed multicrenulated teeth in middle dentary toot- row, a remarkable feature only shared with teleosaurids Machimosaurus hugii (Upper Jurassic of Laurasia) and M. rex (Lower Cretaceous of Tunisia). This apomorphy was also recognized in new material from the Alfredo Marcondes municipality (Presidente Prudente Formation), which are here also referred to "G". paulistanus. We recognized the teeth of "G." paulistanus as the lectotype, however the tibia cannot be assigned to a species as it was not collected in association with the teeth. We performed a phylogenetic analysis with a data matrix composed of 388 characters and 86 taxa, analyzed in TNT. The strict consensus tree recovered Neosuchia and Ziphosuchia (Notosuchia + Sebecia) within Mesoeucrocodylia. The species "G" paulistanus is valid, as a distinct and new genus within Sebecia, in a polytomy with Barreirosuchus, Pepesuchus, Itasuchus and Peirosaurus, forming the clade Itasuchidae. Stolokrosuchus is the sister taxon to Itasuchidae, the sister group of all other Sebecia (Peirosauridae (Mahajangasuchidae + Sebecidae and taxa affinis)). The clades Ziphosuchia, Sebecia and Itasuchidae are here redefined, and we find the last two clades to be more closely related to terrestrial notosuchids than to semiaquatic neosuchians.

The genus Hoplophorus is one of the most distinctive glyptodonts from the Quaternary deposits of the intertropical area of Brazil. In this paper, we redescribe cranial and postcranial elements and describe some new tarsal elements belonging to the species Hoplophorus euphractus from caves from Minas Gerais state, southern Brazil, in order to provide a better diagnosis for the genus. The material examined shows several striking, distinctive characters relative to Neosclerocalyptus, besides those previously reported, reinforcing the validity of Hoplophorus. On the other hand, we find that the postcrania of Hoplophorus presents striking, unreported resemblances with Panochthus (e.g., more lateromedially elongated cuboid facet of navicular and caudal tube with large lateral figures separated from the terminal ones by a wide space). In order to infer the relationships of Hoplophorus and to reevaluate the monophyly of the tribe Hoplophorini and the subfamily Hoplophorinae (in which Hoplophorus was previously allocated), we carried out a cladistic analysis of 18 taxa, including 13 glyptodont genera and five cingulate outgroups, scored for 151 cranial, dental, and postcranial characters. The most parsimonious tree shows that Hoplophorinae and Hoplophorini are both paraphyletic and has Hoplophorus as the sister group to Panochthus based mostly on synapomorphies of the caudal tube. We propose: (1) restricting the definition of the tribe Hoplophorini to the lineage represented by Hoplophorus, making it the sister group to Panochthini within Panochthinae (= Hoplophorus + Panochthus); and (2) a new subfamily, Neosclerocalyptinae, represented by Neosclerocalyptus, the sister group to Panochthinae. Fil: Porpino, Kleberson de O.. Universidade Federal do Rio Grande do Norte; Brasil Fil: Fernicola, Juan Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Bergqvist, Lílian P.. Universidade Federal do Rio de Janeiro; Brasil

Pachyarmatherium is an enigmatic cingulate genus formerly recognized as Dasypodoidea, but tentatively assigned to the poorly known subfamily Glyptatelinae (Glyptodontidae) by later authors. A new species is described from the late Pleistocene of northeastern Brazil. The material comprises several isolated osteoderms, carapace fragments, and miscellaneous postcranial material. The new species, Pachyarmatherium brasiliense, differs from the North American Pachyarmatherium leiseyi in being larger and in having osteoderms with heptagonal shape, main figures with oblong, subrounded and polygonal outline (instead of only polygonal), and a larger number of peripheral figures. To clarify the affinities of Pachyarmatherium, a cladistic analysis was conducted of 48 morphological postcranial characters and scored for 11 cingulates (the new species, four dasypodids, one pampathere and five glyptodontids) and two pilosans used as outgroup taxa. In the most parsimonious topology obtained, Pachyarmatherium is t...