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La Pampa province is divided into two clearly distinguishable fractions: a small northeastern humid sector corresponding to the Pampas ecoregion and a drier western sector, represented by the Monte de Llanuras y Mesetas (termed Monte region in this paper) and Espinal ecoregions (sensu Brown et al. 2006). These three ecoregions are visibly distinguishable from an edaphological and phytogeographic point of view, while the mammalian fauna composition is homogeneous. The study area was located in the central part of the province, comprising the Monte and Espinal ecoregions (Fig. 1). In that area three species of armadillos are recorded (Soibelzon et al. 2015). Two of these (Zaedyus pichiy Desmarest, 1804 and Chaetophractus villosus Desmarest, 1804) (Xenarthra: Chlamyphoridae) are the most common and widely distributed armadillos both in the province and in the country, while the third species, Chlamyphorus truncatus Harlan, 1825, has a more restricted distribution and is one of the most cryptic and least known armadillos in the country. For this reason, in our fieldwork ectoparasites were obtained only from the first two species mentioned.

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The jaguar Panthera onca and the Brazilian three-banded armadillo Tolypeutes tricinctus are two threatened mammals that coexist in the Caatinga dry forests and the Cerrado savannas of Brazil. Yet, to the best of our knowledge, interactions between these species have not been reported in the literature. Here, we present the first records of P. onca predation on T. tricinctus from two different areas in the Caatinga in northeastern Brazil. We showed that P. onca can pierce the hard carapace of T. tricinctus, which may be possible due to its distinctly strong bite and associated predation behavior. We argue that P. oncamay be the most adapted non-human predator to feed on T. tricinctus, and that the smaller body sizes of P. onca individuals in the Caatinga may increase their likelihood to feed on smaller prey, including T. tricinctus. Thus, the originality of our records is probably more related to insufficient research in the areas where these species coexist than to the rarity of this interaction.(AU)

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Abstract: Riostegotherium yanei from the Itaboraí 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 diploë-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.

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The Mylodontidae Scelidotheriinae (Mammalia, Xenarthra, Tardigrada) are a diversified clade of South American fossil ground sloths, with a wide geographic distribution, especially in high and middle latitudes. According to the last revision, the Quaternary diversity includes the genera Scelidotherium, Catonyx, and Valgipes. The clade Scelidotheriinae is well represented in the Pleistocene of the Tarija-Padcaya basin, and the first mention of these ground sloths correspond to the middle of the XIX Century. Since then, several species (i.e., Scelidotherium tarijensis, Scelidodon tarijensis, Scelidotherium capellini) have been reported as inhabiting the Tarija-Padcaya basin during the Pleistocene. Despite the abundance of fossil records of Scelidotheriinae in this area, no modern taxonomic revisions are available. In consequence, in this contribution a revision of the remains assigned to Scelidotheriinae from the Tarija-Padcaya basin is accomplished, and some biostratigraphic and geographic implications are discussed. Our results show that one single species (Catonyx tarijensis) can be recognized in the studied area, whereas a supposed smaller one (Scelidotherium patrium) actually corresponds to juvenile specimens of C. tarijensis.

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The relationship between humerus shape and the modes of exploring substrate among extinct and extant Pilosa (especially anteaters and ground sloths) were investigated here. We used geometric morphometrics and discriminant analyses to relate morphological patterns and their possible ecological categories. Our results suggest that plesiomorphic taxa such as Nothrotheriidae, most Megalonychidae and basal Megatheriidae tend to have more slender humerus, associated to generalist habitus (climbing, swimming and digging activities), and while Mylodontidae developed specialized digging habitus. Additionally, we inferred ground sloths which inhabited the Brazilian territory during the Quaternary likely occupied at least four different niches. Mammals display morphofunctional adaptations on the limbs which are reflected on their modes of substrate exploration. Herein, we analyzed the humerus morphology of ground sloths and anteaters. Our results suggest that most of the Pleistocene Mylodonts were fossorial taxa, while most of the Santacrucian sloths plus extant anteaters were semiarboreal or semiaquatic taxa. The Pleistocene Megatheriidae should be ambulatory.

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Mylodon darwinii is the extinct giant ground sloth named after Charles Darwin, who first collected its remains in South America. We have successfully obtained a high-quality mitochondrial genome at 99-fold coverage using an Illumina shotgun sequencing of a 12 880-year-old bone fragment from Mylodon Cave in Chile. Low level of DNA damage showed that this sample was exceptionally well preserved for an ancient subfossil, probably the result of the dry and cold conditions prevailing within the cave. Accordingly, taxonomic assessment of our shotgun metagenomic data showed a very high percentage of endogenous DNA with 22% of the assembled metagenomic contigs assigned to Xenarthra. Additionally, we enriched over 15 kb of sequence data from seven nuclear exons, using target sequence capture designed against a wide xenarthran dataset. Phylogenetic and dating analyses of the mitogenomic dataset including all extant species of xenarthrans and the assembled nuclear supermatrix unambiguously place Mylodon darwinii as the sister-group of modern two-fingered sloths, from which it diverged around 22 million years ago. These congruent results from both the mitochondrial and nuclear data support the diphyly of the two modern sloth lineages, implying the convergent evolution of their unique suspensory behaviour as an adaption to arboreality. Our results offer promising perspectives for whole-genome sequencing of this emblematic extinct taxon.

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Several detailed studies of the external morphology of the ear region in extinct sloths have been published in the past few decades, and this anatomical region has proved extremely helpful in elucidating the phylogenetic relationships among the members of this mammalian clade. Few studies of the inner ear anatomy in these peculiar animals were conducted historically, but these are increasing in number in recent years, in both the extinct and extant representatives, due to wider access to CT-scanning facilities, which allow non-destructive access to internal morphologies. In the present study, we analyze the extinct ground sloth Glossotherium robustum and provide a description of the external features of the ear region and the endocranial side of the petrosal bone, coupled with the first data on the anatomy of the bony labyrinth. Some features observable in the ear region of G. robustum (e.g., the shape and size of the entotympanic bone and the morphology of the posteromedial surface of the petrosal) are highly variable, both intraspecifically and intraindividually. The form of the bony labyrinth of G. robustum is also described, providing the first data from this anatomical region for the family Mylodontidae. The anatomy of the bony labyrinth of the genus Glossotherium is here compared at the level of the superorder Xenarthra, including all available extant and extinct representatives, using geometric morphometric methods. In light of the new data, we discuss the evolution of inner ear anatomy in the xenarthran clade, and most particularly in sloths, considering the influence of phylogeny, allometry, and physiology on the shape of this highly informative region of the skull. These analyses show that the inner ear of Glossotherium more closely resembles that of the extant anteaters, and to a lesser extent those of the giant ground sloth Megatherium and euphractine armadillos, than those of the extant sloths Bradypus and Choloepus, further demonstrating the striking morphological convergence between the two extant sloth genera.

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A large diversity of Glyptodontidae has been proposed as characterizing the Chapadmalalan Age (Pliocene). Most of these taxa were recognized on the basis of partial dorsal carapaces and/or caudal tubes, whereas the main diagnostic characteristic is a particular morphology of the exposed surface of the osteoderms. From a biostratigraphic point of view some species are biostratigraphically important. The Upper Chapadmalalan is based on the Paraglyptodon chapadmalensis biozone. Both the re-evaluation of the type and referred materials and new significant findings from the Chapadmalal and El Polvorín Formations indicate that the diversity of Pliocene Glyptodontidae is more limited than previously supposed. The particular morphology of the exposed surface of the osteoderms that characterizes some of the species actually corresponds to a taphonomic alteration, which results in a non-real ornamentation pattern. Thus, the Glyptodontinae P. chapadmalensis must be replaced as a fossil guide because neither this species nor the species included in the genera Urotherium, Trachycalyptus and Lomaphorus are well characterized. Taking into account the diversity of Glyptodontidae for this lapse, the Glyptodontinae are very scarce (a situation that contrasts with its records in the Pleistocene), whereas Eosclerocalyptus, "Plohophorini" (Plohophorus) and Doedicurinae (cf. Eleutherocercus antiquus) are among the most recorded taxa.

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The hairy long-nosed armadillo, currently referred as Dasypus (Cryptophractus) pilosus, is an enigmatic species endemic to montane cloud forests and subparamo of Peruvian Andes. Its strikingly different external features, which include the carapace concealed by abundant hair, the presence of more movable bands, and a slender skull, have raised questions regarding its taxonomic status as subgenus or as genus. This paper assesses this issue based on a cladistic study and provides a detailed comparative description of the species, including the first account on the distinctive ornamentation of its osteoderms. Based on several unique characters in the carapace, skull, mandible, and teeth, as well as on the external phylogenetic position relative to other Dasypus, we favor the assignment of the hairy long-nosed armadillo to other genus. As result, we revalidate the original generic epithet, so that the valid name of the species is Cryptophractus pilosus Fitzinger, 1856.

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The genus Panochthus represents the last lineage of "Panochthini" recorded in the Pleistocene. This genus has a wide latitudinal distribution in South America, and in Brazil it occurs in the southern and northeastern regions. In this paper we describe new material (isolated osteoderms and caudal tube fragments) assigned to Panochthus from the state of Rio Grande do Sul (southern Brazil) and discuss some taxonomic issues related to Panochthus tuberculatus and Panochthus greslebini based on this material . The occurrence of P. greslebini is the first for outside the Brazilian Intertropical Region. In addition, we describe new diagnostic features to differentiate the osteoderms of P. greslebini and P. tuberculatus. Unfortunately, it was not possible to identify some osteoderms at the species level. Interestingly, they showed four distinct morphotypes characterized by their external morphology, and thus were attributed to Panochthus sp. Lastly, we conclude that in addition to P.tuberculatus registered to southern Brazil, there is another species of the genus, assignable to P. cf. P. greslebini. Our analysis reinforce the reliability of caudal tube characters for the classification of species of Panochthus.

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This paper deals with xenarthrans osteoderms assigned to Dasypus aff. D. novemcinctus, Euphractus sexcinctus and Cabassous sp. The material was collected in subsurface, from 0.10 to 0.60 m in the Urso Fóssil Cave, Parque Nacional de Ubajara, State of Ceará, northeastern Brazil. The ages of sediment samples from levels 4 and 5 (depths of 0.40 and 0.50 m) were determined by thermoluminescence technique, and indicated ages of 8,000 and 8,200 years BP for each layer respectively. The presence in these layers of early Holocene xenarthrans taxa can contribute to the understanding of the biotic evolution of the northwest region of Ceará during the last 10,000 years. Two of the three identified taxa still occur in the region: Dasypus novemcinctus and Euphractus sexcinctus. The Dasypodidae fauna here reported includes animals with generalist feeding habits and current wide geographical distribution. It is suggested, therefore, that the climatic and environmental conditions in the early Holocene were very similar the actual ones, and that the absence of Cabassous may be conditioned to other factors, such as anthropogenic action and loss of habitat by fragmentation of the vegetation.

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Dextrocardia is a rare cardiac anomaly where the heart is situated on the right antimeres of the thorax. This study had the objective of describing a case of dextrocardia with situs solitus and apex-basis axis inversion in a lesser anteater (Tamandua tetradactyla) between five evaluated animals, all from the area of Mine Bauxite - Paragominas - Para. The arterial system was filled with contrasted latex and the animals were fixed with 10% formaldehyde and a posterior dissection was done. The heart of an animal was found in right antimere with inversion of the base-apex axis. The right atrium was more developed then the left and the pulmonary veins arrived directly in the left ventricle. The main vases of the base were identified with some topographic alterations resulting in: aorta dorsal to the cava caudal vein, pulmonary artery dorsal and cranial to aorta, pulmonary veins ventral to the pulmonary artery, cava caudal vein in ventral plain and cava cranial vein in dorsal plan in relation to the other vessels. Internally there were four cardiac chambers, with absence of septal communication.

Dextrocardia é uma anomalia cardíaca rara no qual o coração está situado no antímero direito do tórax. Este estudo objetivou descrever um caso de dextrocardia com situs solitus e inversão do eixo ápice-base em um tamanduá-mirim (Tamandua tetradactyla), entre cinco animais avaliados, sendo todos da área da mina de bauxita - Paragominas - Pará. O sistema arterial foi preenchido com látex contrastado e os animais foram fixados com formol a 10% e seguido de dissecção posterior. O coração de um dos animais foi encontrado no antímero direito com inversão do eixo ápice-base. O átrio direito era mais desenvolvido do que o esquerdo e as veias pulmonares chegaram direto no ventrículo esquerdo. Foram identificados os principais vasos da base com alterações topográficas, resultando em: aorta dorsal à veia cava caudal, artéria pulmonar dorsal e cranial da aorta, veias pulmonares ventrais a artéria pulmonar, veia cava caudal em plano ventral e veia cava cranial em plano dorsal em relação a outros vasos. Internamente foram localizadas quatro câmaras cardíacas, com ausência de comunicação septal.

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RESUMO

Dextrocardia is a rare cardiac anomaly where the heart is situated on the right antimeres of the thorax. This study had the objective of describing a case of dextrocardia with situs solitus and apex-basis axis inversion in a lesser anteater (Tamandua tetradactyla) between five evaluated animals, all from the area of Mine Bauxite - Paragominas - Para. The arterial system was filled with contrasted latex and the animals were fixed with 10% formaldehyde and a posterior dissection was done. The heart of an animal was found in right antimere with inversion of the base-apex axis. The right atrium was more developed then the left and the pulmonary veins arrived directly in the left ventricle. The main vases of the base were identified with some topographic alterations resulting in: aorta dorsal to the cava caudal vein, pulmonary artery dorsal and cranial to aorta, pulmonary veins ventral to the pulmonary artery, cava caudal vein in ventral plain and cava cranial vein in dorsal plan in relation to the other vessels. Internally there were four cardiac chambers, with absence of septal communication.(AU)

Dextrocardia é uma anomalia cardíaca rara no qual o coração está situado no antímero direito do tórax. Este estudo objetivou descrever um caso de dextrocardia com situs solitus e inversão do eixo ápice-base em um tamanduá-mirim (Tamandua tetradactyla), entre cinco animais avaliados, sendo todos da área da mina de bauxita - Paragominas - Pará. O sistema arterial foi preenchido com látex contrastado e os animais foram fixados com formol a 10% e seguido de dissecção posterior. O coração de um dos animais foi encontrado no antímero direito com inversão do eixo ápice-base. O átrio direito era mais desenvolvido do que o esquerdo e as veias pulmonares chegaram direto no ventrículo esquerdo. Foram identificados os principais vasos da base com alterações topográficas, resultando em: aorta dorsal à veia cava caudal, artéria pulmonar dorsal e cranial da aorta, veias pulmonares ventrais a artéria pulmonar, veia cava caudal em plano ventral e veia cava cranial em plano dorsal em relação a outros vasos. Internamente foram localizadas quatro câmaras cardíacas, com ausência de comunicação septal.(AU)

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Tamandua tetradactyla (Pilosa), the lesser anteater, is a medium-size mammal from South America. Its wide distribution through different landscapes, solitary and nocturnal habits, and the difficulty to capture and contain specimens limit the amount of individuals and populations sampled during fieldworks. These features along with the lack of specific molecular markers for the lesser anteater might be the causes for paucity in population genetic studies for the species. Historical samples from museum specimens, such as skins, and non-invasive samples, such as plucked hair, can be supplementary sources of DNA samples. However, the DNA quantity and quality of these samples may be limiting factors in molecular studies. In this study, we describe nine microsatellite loci for T. tetradactyla and test the amplification success, data reliability and estimate errors on both historical and non-invasive sample sets. We tested nine polymorphic microsatellites and applied the quality index approach to evaluate the relative performance in genotype analysis of 138 historical samples (study skin) and 19 non-invasive samples (plucked hair). The observed results show a much superior DNA quality of non-invasive over historical samples and support the quality index analysis as a practical tool to exclude samples with doubtful performance in genetic studies. We also found a relationship between the age of non-invasive samples and DNA quality, but lack of evidence of this pattern for historical samples.

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O tamanduá-mirim (Tamandua tetradactyla) é um xenartro da família Myrmecophagidae, encontrado da Venezuela ao sul do Brasil. Estudos apontam que essa é uma das espécies de animais selvagens mais vitimadas em número de atropelamentos, e, muitas vezes, o atendimento clínico adequado aos indivíduos feridos é dificultado pela carência de informações acerca dos mesmos. Visando contribuir com o conhecimento dessa espécie, este estudo teve como objetivo descrever seu plexo lombossacral. Para tanto, foram utilizados quatro cadáveres de Tamandua tetradactyla adultos e de ambos os sexos. O plexo lombossacral dessa espécie é formado pelos ramos ventrais dos nervos espinhais T18, L1, L2, L3, S1, S2, S3, S4, S5. Os nervos integrantes do plexo lombossacral do T. tetradactyla com suas formações mais frequentes foram os seguintes: genitofemoral (T18), cutâneo femoral lateral (T18-L1), femoral (T18, L1-L3), obturador (T18, L1-L3), glúteo cranial (L3-S1), isquiático (L3-S3), pudendo (S3-S4 ou S4-S5), retal caudal (S4 ou S5) e cutâneo femoral caudal (S4-S5). O plexo lombar e sacral dessa espécie é unido, sendo L3 o ponto de união entre eles. Devido ao pequeno número de vértebras lombares, a composição dos nervos do plexo lombossacral do T. tetradactyla apresenta características peculiares que se diferem das características das demais espécies já estudadas, quais sejam, a ausência dos nervos ílio-hipogástrico e ilioinguinal e participação de nervos torácicos na composição dos nervos do plexo lombar, presença de contribuição sacral na composição do nervo obturador e ausência de contribuição lombar na composição do nervo isquiático e um limite mais caudal na extensão do plexo sacral.

The lesser anteater (Tamandua tetradactyla) is a xenarthra of the Myrmecophagidae family found from Venezuela to southern Brazil. Studies have shown that this is one of the most numerous wildlife species victims of car collisions on roads, and often the appropriate clinical care to injured animals is hindered by the lack of information about them. In order to contribute to the knowledge of this species, this study aimed to describe its lumbosacral plexus. For this purpose, four cadavers of adult specimens of both sexes of T. tetradactyla were used. The lumbosacral plexus of the T. tetradactyla is formed by the ventral rami of spinal nerves T18, L1, L2, L3, S1, S2, S3, S4, S5. The lumbosacral plexus nerves with their most common formations in this species were as follows: genitofemoral (T18), lateral femoral cutaneous (T18-L1), femoral (T18, L1-L3), obturator (T18, L1-L3), cranial gluteal (L3-S1), ischiatic (L3-S3), pudendus (S3-S4 or S4-S5), caudal retal (S4 or S5), and caudal femoral cutaneous (S4-S5). The lumbar and sacral plexus of this species is joined, L3 being the link between them. Due to the small number of lumbar vertebrae, the arrangement of the lumbosacral plexus nerves of the T. tetradactyla showed peculiar characteristics that differ it from that of other previously studied species, such as the absence of iliohypogastric and ilioinguinal nerves and contribution of thoracic nerves in the formation of all the nerves of the lumbar plexus, presence of sacral contribution in the formation of the obturator nerve, and the lack of lumbar contribution for sciatic nerve formation and a most caudal extent of the sacral plexus.

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O tamanduá-mirim (Tamandua tetradactyla) é um xenartro da família Myrmecophagidae, encontrado da Venezuela ao sul do Brasil. Estudos apontam que essa é uma das espécies de animais selvagens mais vitimadas em número de atropelamentos, e, muitas vezes, o atendimento clínico adequado aos indivíduos feridos é dificultado pela carência de informações acerca dos mesmos. Visando contribuir com o conhecimento dessa espécie, este estudo teve como objetivo descrever seu plexo lombossacral. Para tanto, foram utilizados quatro cadáveres de Tamandua tetradactyla adultos e de ambos os sexos. O plexo lombossacral dessa espécie é formado pelos ramos ventrais dos nervos espinhais T18, L1, L2, L3, S1, S2, S3, S4, S5. Os nervos integrantes do plexo lombossacral do T. tetradactyla com suas formações mais frequentes foram os seguintes: genitofemoral (T18), cutâneo femoral lateral (T18-L1), femoral (T18, L1-L3), obturador (T18, L1-L3), glúteo cranial (L3-S1), isquiático (L3-S3), pudendo (S3-S4 ou S4-S5), retal caudal (S4 ou S5) e cutâneo femoral caudal (S4-S5). O plexo lombar e sacral dessa espécie é unido, sendo L3 o ponto de união entre eles. Devido ao pequeno número de vértebras lombares, a composição dos nervos do plexo lombossacral do T. tetradactyla apresenta características peculiares que se diferem das características das demais espécies já estudadas, quais sejam, a ausência dos nervos ílio-hipogástrico e ilioinguinal e participação de nervos torácicos na composição dos nervos do plexo lombar, presença de contribuição sacral na composição do nervo obturador e ausência de contribuição lombar na composição do nervo isquiático e um limite mais caudal na extensão do plexo sacral.(AU)

The lesser anteater (Tamandua tetradactyla) is a xenarthra of the Myrmecophagidae family found from Venezuela to southern Brazil. Studies have shown that this is one of the most numerous wildlife species victims of car collisions on roads, and often the appropriate clinical care to injured animals is hindered by the lack of information about them. In order to contribute to the knowledge of this species, this study aimed to describe its lumbosacral plexus. For this purpose, four cadavers of adult specimens of both sexes of T. tetradactyla were used. The lumbosacral plexus of the T. tetradactyla is formed by the ventral rami of spinal nerves T18, L1, L2, L3, S1, S2, S3, S4, S5. The lumbosacral plexus nerves with their most common formations in this species were as follows: genitofemoral (T18), lateral femoral cutaneous (T18-L1), femoral (T18, L1-L3), obturator (T18, L1-L3), cranial gluteal (L3-S1), ischiatic (L3-S3), pudendus (S3-S4 or S4-S5), caudal retal (S4 or S5), and caudal femoral cutaneous (S4-S5). The lumbar and sacral plexus of this species is joined, L3 being the link between them. Due to the small number of lumbar vertebrae, the arrangement of the lumbosacral plexus nerves of the T. tetradactyla showed peculiar characteristics that differ it from that of other previously studied species, such as the absence of iliohypogastric and ilioinguinal nerves and contribution of thoracic nerves in the formation of all the nerves of the lumbar plexus, presence of sacral contribution in the formation of the obturator nerve, and the lack of lumbar contribution for sciatic nerve formation and a most caudal extent of the sacral plexus.(AU)

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Untangling the root of the evolutionary tree of placental mammals has been nearly an impossible task. The good news is that only three possibilities are seriously considered. The bad news is that all three possibilities are seriously considered. Paleontologists favor a root anchored by Xenarthra (e.g., sloths and anteater), whereas molecular evolutionists have favored the two other possible roots: Afrotheria (e.g., elephants, hyraxes, and tenrecs) and Atlantogenata (Afrotheria + Xenarthra). Now, two groups of researchers have scrutinized the largest available genomic data sets bearing on the question and have come to opposite conclusions, as reported in this issue of Molecular Biology and Evolution. Needless to say, more research is needed.

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Among South American Quaternary Glyptodontidae (Mammalia, Cingulata), Neosclerocalyptus Paula Couto represents one of the best known genera. Prior to this contribution, four species were recognized. N. pseudornatus (Ameghino) and N. ornatus (Owen) (Ensenadan Age/Stage, early-middle Pleistocene); N. gouldi Zurita (Bonaerian Age/Stage, middle Pleistocene-late Pleistocene), and N. paskoensis (Zurita) (Lujanian Age/Stage, late Pleistocene-early Holocene). One of the most notable characters of the species of the genus is a modified area located in the distal part of the nasals, recently interpreted as a neomorphic structure derived from the ossification of the nasal cartilages. In this contribution, a new species of Neosclerocalyptus (N. castellanosi sp. nov.), which in turn represents the oldest record of the genus, is presented and described. In addition, a cladistic analysis is carried out to test the monophyly of Neosclerocalyptus and the phylogenetic position of this new species. The material comes from Vorohuean (late Pliocene) levels in the surroundings of Mar del Plata, Buenos Aires Province, Argentina. Among other morphological characters, this new species has ossified nasal cartilages restricted to the latero-dorsal area of the nasals, whereas in the remaining species these structures are more expanded and both sides contact in the midline of the skull. In turn, the phylogenetic analysis confirmed the monophyly of Neosclerocalyptus, whereas N. castellanosi sp. nov. appears closely related to N. pseudornatus, being N. ornatus the sister taxa of this clade. On the other hand, N. gouldi + N. paskoensis constitute the other clade. The clade constituted by Hoplophorus euphractus Lund + Panochthus intermedius Lydekker constitutes the sister taxa of Neosclerocalyptus.

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Urbanization poses a serious threat to wildlife populations inhabiting native vegetation remnants surrounded by the expanding urban and suburban sprawl. The close contact with human activities causes not only direct impacts, such as habitat loss, but also indirect negative effects, such as population isolation, roadkills and anthropogenic fires. The Parque Nacional de Brasília is a large Cerrado remnant almost completely surrounded by the city of Brasília, in central Brazil. Here, we use population viability analysis to model the impacts of urbanization on a population of Myrmecophaga tridactyla (Linnaeus, 1758) inhabiting that park. Our results show that roadkill mortality is by far the most serious threat to the long-term persistence of the giant anteater in the study site. The implementation of measures to better control vehicle speed in the vicinity of the park is urgently needed if we expect the giant anteater population to be effectively protected in the Parque Nacional de Brasília.(AU)

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Urbanization poses a serious threat to wildlife populations inhabiting native vegetation remnants surrounded by the expanding urban and suburban sprawl. The close contact with human activities causes not only direct impacts, such as habitat loss, but also indirect negative effects, such as population isolation, roadkills and anthropogenic fires. The Parque Nacional de Brasília is a large Cerrado remnant almost completely surrounded by the city of Brasília, in central Brazil. Here, we use population viability analysis to model the impacts of urbanization on a population of Myrmecophaga tridactyla (Linnaeus, 1758) inhabiting that park. Our results show that roadkill mortality is by far the most serious threat to the long-term persistence of the giant anteater in the study site. The implementation of measures to better control vehicle speed in the vicinity of the park is urgently needed if we expect the giant anteater population to be effectively protected in the Parque Nacional de Brasília.

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