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Abstract A new early Eocene, small-sized metatherian from the Itaboraí fauna is described. The new taxon is recognized on the basis of an incomplete dentary recovered from fissure fillings in the travertine limestones from the Itaboraí Basin, State of Rio de Janeiro, Brazil. The phylogenetic analysis placed the new genus and species as the sister taxon of Derorhynchus, undescribed Derorhynchidae, and Coona plus Pauladelphys. When compared to Derorhynchus, the new taxon exhibits a shorter dentary, in which the first lower premolar is not separated from the second by a diastema, and shows second and third lower molars with subequal trigonid and talonid width (in Derorhynchus the talonids are wider than the trigonids). This new taxon shows some plesiomorphic traits when compared with the remaining derorhynchids, such as the shallower dentary (less than 1.5 mm), and conical entoconids rather than flattened in shape. The combination of very small size (~13-20g), sharp crests, tall and slender cuspids, broad talonid basins, as well as trigonid taller than the talonid is suggestive of an insectivorous diet for the new taxon.

Zeusdelphys complicatus is one of the most enigmatic metatherians from the Itaboraí Basin. The type and only known specimen was previously regarded as the upper dentition of Eobrasilia; an M4 of a new taxon; an M3 of a Kollpaniidae (now regarded as a group of “condylarths”); a probable M1 of an incertae sedis taxon; and as an M1 of a Protodidelphidae. Herein, we present a morphological review of the dental structures of Zeusdelphys complicatus, presenting new interpretations and comparing it with other North and South American taxa. We also perform a phylogenetic analysis in order to test the affinities of Zeusdelphys and the validity of most studied characters. The results recovered Zeusdelphys complicatus as more closely related to Hatcheritherium alpha than to any other metatherian. Glasbiidae were recovered as the sister lineage of Protodidelphidae within Didelphimorphia, as true marsupials. Ectocentrocristus was recovered as the sister taxon of Zeusdelphys + Hatcheritherium, as a Hatcheriformes. The analysis recovered this suborder as an independent lineage from Polydolopimorphia, being more closely related to “Alphadontidae”. The affinities with Protodidelphidae are a result of convergent evolution, as Zeusdelphys is more closely related to Hatcheritherium alpha from the Late Cretaceous of North America. The results support a North American origin for Hatcheriformes. The presence of strong sea-level lowstands and islands in the Caribbean Plate during the Late Cretaceous provide valid data to support a faunal interchange between Americas during the latest Late Cretaceous. Based on the results, Zeusdelphys represents a South American early Eocene surviving Hatcheriformes.

To verification of quali-quantitative it has been accomplished collected of bivalve molluscs during the period of twelve months, together with analysis of some abiotic variables in the middle care of Uruguay river, situated in São Marcos, Uruguaiana municipality. The place where the collects has been accomplished, were divided in three distinct spots, considerating the substract type predominant; sand, rock and mud. The individuals were collected using hands and with. The selection screen aid, of 0.8mm size net and were conserved in a dry environment. They had been collected a total of 1,022 units of bivalves, wich belong to 12 taxa, being that of these only specimens Cyanocyclas limosa and Diplodon parallelopipedon had been captured alive (tanatocenosis). It had great quantitative predominance of Corbicula fluminea and Diplodon uruguayensis. With exception of bivalves invading, the too much species had been collected only in the slimy substratum. Other species occurrence were Mycetopoda siliquosa and Anodontites trigonus, there two species a vulnerable to extinction in Rio Grande do Sul.

Abstract The Toca das Onças cave is one of the most important Quaternary mammal deposits of Brazil. Two different hypotheses have been proposed to explain the preservation mode of its skeletal remains: either the animals climbed down into the cave, or it could have functioned as a natural trap. Evaluation of pathological modifications on three articulated vertebrae of a single adult giant ground sloth Eremotherium laurillardi reveals a particular type of bone fracture caused by compressive force on the vertebral column, which split the vertebral bodies in the sagittal plane. This diagnosis suggests that the animal accidentally fell into the cave, in accordance with the second hypothesis proposed to the incorporation mode of skeletal remains into the cave.

Este trabalho descreve marcas encontradas em fósseis de mamíferos pleistocênicos do Sítio Lagoa da Pedra, que fica localizado no distrito de Conceição das Creoulas, identificando possíveis relações temporais e/ou físicas entre os grupos pré-históricos e a megafauna que coabitou a região nordeste do Brasil, em Salgueiro - PE, no Pleistoceno Final - Holoceno Inicial. A metodologia aplicada, utilizando microscópio estereoscópico, identificou fósseis que apresentam marcas que foram possivelmente causadas por instrumentos líticos. O trabalho apresenta indícios de interação homem-megafauna através da caça desses animais, reforçando evidências já existentes sobre a coabitação durante o final do Pleistoceno e início do Holoceno. BRANDS ON MEGAFAUNA FOSSILS IN LAGOA DA PEDRA, SALGUEIRO-PE, BRAZIL ABSTRACT This work describes marks found on fossil mammals of the Pleistocene Lagoa da Pedra Site, which is located in the Conceição das Creoulas district, identifying possible temporal and / or physical relationships between prehistoric groups and the megafauna that cohabitated the northeast region of Brazil. , in Salgueiro - PE, in the Late Pleistocene - Early Holocene. The applied methodology, using stereoscopic microscope, identified fossils presenting marks that were possibly caused by lithic instruments. This work presents evidence of human-megafauna interaction through hunting of these animals, reinforcing existing evidence on cohabitation during the late Pleistocene and early Holocene. Keywords: Quaternary; marks; fossils; pleistocene mammals; megamammals.

O presente trabalho versa sobre novas ocorrências de lenhos fósseis nos municípios de Missão Velha, Abaiara e Milagres, bem como investiga suas características tafonômicas e sedimentológicas. Os fósseis observados podem ser categorizados em três estágios sequenciais de exposição: lenhos in situ, presentes em seu depósito original; lenhos exumados, resultantes da denudação da rocha hospedeira; e lenhos ex situ, deslocados por transporte sedimentar ou por ação antrópica. Os lenhos in situ podem ser primários, correspondendo a uma assembleia alóctone, ou secundários, lenhos silicificados retrabalhados que se comportam como seixos nos arenitos da unidade. Lenhos de grande porte foram pouco transportados e estão próximos aos sítios de fossilização. Fragmentos de lenhos muito degradados confundem-se com cascalho e um estudo petrográfico como este pode auxiliar na sua identificação.

Arthritic lesions have been frequently diagnosed in the fossil record, with spondyloarthropathy (a type of erosive and pan-mammalian arthritis) being one of the most common types described to date for mammals, though not restricted to this group. Here, we identify spondyloarthropathy in fossil bones from the late Pleistocene in Brazil assignable to a large glyptodont individual. Bone erosions in the peripheral joints (viz., the ulna, radius, left femur and tibiae-fibulae) associated with osteosclerosis allow the diagnosis of spondyloarthropathy. The presence of osteophytes in seven bones of the forelimbs (viz., the ulna and radius) and hind limbs (viz., the tibiae-fibulae, left femur and patellae) and a subchondral cyst in one element (viz., the left femur) indicate secondary osteoarthritis. A calcified deposition on the articular surface of the left patella indicates the presence of calcium pyrophosphate deposition disease, which, like the observed osteoarthritic alterations, likely represents a complication of spondyloarthropathy. This is the first report of spondyloarthropathy for xenarthrans.