Gisele Lessa

A new genus of sigmodontine rodent from eastern Brazil and the origin of the tribe Phyllotini

Abstract We describe a new living genus and species of Sigmodontinae currently only known from the Brazilian National Park Sempre Vivas, Minas Gerais State. This rodent is characterized by a unique combination of traits that include, among others, a long tail, with its distal tip (approximately 2.5 to 5 cm) entirely white; skull with domed profile; long rostrum with an incipient rostral tube; and noticeable small brachyodont molars with reduced mesolophs and mesostyles present on the 1st and 2nd upper molars. Cladistic analyses of molecular (1 mitochondrial and 1 nuclear marker) and morphological characters indicate that the new genus belongs to the Phyllotini and is sister to the remainder genera of this tribe. However, contrary to other known phyllotines, the new genus shows vestigial mesolophs and mesostyles. Phyllotines are widespread in open areas, in particular desert and semideserts, mostly in the western portion of South America. The new genus described herein expands the diversity of the tribe and suggests an ancient event of diversification in eastern Brazil. Resumen Describimos un nuevo género y especie de Sigmodontinae actualmente sólo conocido para el Parque Nacional brasilero Sempre Vivas, Estado de Minas Gerais. Este roedor se caracteriza por una combinación única de rasgos que incluyen, entre otros, una cola larga con su porción distal (ca. 2,5 a 5 cm) enteramente blanca; cráneo con perfil abovedado; rostro largo con tubo rostral incipiente; molares braquiodontos notablemente pequeños con pequeños mesolofos y mesostilos presentes en los primeros y segundos molares superiores. Análisis cladísticos de caracteres moleculares (un marcador mitocondrial y un marcador nuclear) y morfológicos indican que el nuevo género pertenece a los Phyllotini y es hermano de los restantes géneros de la tribu. Sin embargo, contrariamente a los otros filotinos conocidos, el nuevo género muestra mesolofos y mesostilos vestigiales. Los filotinos están ampliamente distribuidos en zonas abiertas, en particular en desiertos y semidesiertos, mayormente en la porción occidental de América del Sur. El nuevo género aquí descripto expande la diversidad de la tribu y sugiere un antiguo evento de diversificación en Brasil oriental.

ATLANTIC‐CAMTRAPS: a dataset of medium and large terrestrial mammal communities in the Atlantic Forest of South America

Our understanding of mammal ecology has always been hindered by the difficulties of observing species in closed tropical forests. Camera trapping has become a major advance for monitoring terrestrial mammals in biodiversity rich ecosystems. Here we compiled one of the largest datasets of inventories of terrestrial mammal communities for the Neotropical region based on camera trapping studies. The dataset comprises 170 surveys of medium to large terrestrial mammals using camera traps conducted in 144 areas by 74 studies, covering six vegetation types of tropical and subtropical Atlantic Forest of South America (Brazil and Argentina), and present data on species composition and richness. The complete dataset comprises 53,438 independent records of 83 species of mammals, includes 10 species of marsupials, 15 rodents, 20 carnivores, eight ungulates and six armadillos. Species richness averaged 13 species (±6.07 SD) per site. Only six species occurred in more than 50% of the sites: the domestic dog Canis familiaris, crab-eating fox Cerdocyon thous, tayra Eira barbara, south American coati Nasua nasua, crab-eating raccoon Procyon cancrivorus and the nine-banded armadillo Dasypus novemcinctus. The information contained in this dataset can be used to understand macroecological patterns of biodiversity, community, and population structure, but also to evaluate the ecological consequences of fragmentation, defaunation, and trophic interactions.

Late Quaternary Caviomorph Rodents (Rodentia: Hystricognathi) from Ceará State, Northern Brazil

In this paper we report the first remains of caviomorph rodents from the karst of the Parque Nacional de Ubajara, CearaState, northeastern Brazil, collected with precise stratigraphic and radiometric control. The material is derived from levels with thermoluminescence dating of about 8,000 years BP, corresponding to the early Holocene. In these levels, we found remains of Kerodon rupestris Wied, 1820, cf. Dasyprocta Illiger, 1811 and Thrichomys Trouessart, 1880. The data here reported contribute to the knowledge of Brazilian Quaternary rodents and show the potential of the studied area for fossils.

The genus Abrawayaomys Cunha and Cruz, 1979 (Rodentia: Cricetidae: Sigmodontinae): geographic variation and species definition

Abrawayaomys is a genus endemic to the Atlantic Forest with unique craniodental attributes within the radiation of sigmodontine rodents. Recent data hypothesized the existence of 2 species of Abrawayaomys, namely A. ruschii (from the Brazilian states of Espírito Santo, Rio de Janeiro, and São Paulo) and A. chebezi (from the Argentinean province of Misiones and the Brazilian state of Paraná), as well as a possible undescribed species (from the Brazilian state of Minas Gerais). Herein, based on a large series of recently collected specimens, we assessed the congruence between morphologic and molecular characters to search for discontinuities on these features across geography to delimit species within the genus, testing the aforementioned hypothesis. Morphological analyses, both qualitative and quantitative, showed that all characters are polymorphic throughout the geographic range of the genus. Results from phylogenetic analyses of cytochrome b (Cytb) data showed the topology (Misiones (Minas Gerais (São Paulo, Rio de Janeiro))), which is better explained as geographic rather than taxonomic variation, based on low values of genetic divergence observed between all specimens. Therefore, we reject the hypothesis of a polytypic Abrawayaomys, synonymizing A. chebezi to A. ruschii, and do not recognize specimens from Minas Gerais state as representing a distinct species.

Rediscovery of Lonchophylla bokermanni Sazima, Vizotto and Taddei, 1978 (Chiroptera: Phyllostomidae: Lonchophyllinae) in Minas Gerais, and new records for Espírito Santo, southeastern Brazil

We report the rediscovery of Lonchophylla bokermanni – a species threatened by extinction in Brazil – in Minas Gerais after 25 years (where it was known only from the type-locality), and add three new localities from Espirito Santo, southeastern Brazil. The external and craniodental measurements of the additional specimens fall within the expected range of values for L. bokermanni , although specimens from the Atlantic Rainforest (Rio de Janeiro and Espirito Santo) show a tendency to be smaller.

Proteomes and morphological features of Calomys tener and Necromys lasiurus (Cricetidae, Sigmodontinae) epididymides

Environmental factors, including exposure to anthropogenic factors such as endocrine disruptors, can affect the luminal fluid of the epididymides in which sperm reside during maturation, causing male reproductive dysfunction. We describe and compare epididymal morphology, histomorphometry, and proteomes of Calomys tener and Necromys lasiurus, 2 species of South American sigmodontine rodent whose reproductive biology has been little studied. Five C. tener and 6 N. lasiurus were collected in a protected area of Atlantic Forest (Minas Gerais State, Brazil), where exposure to anthropogenic influences should be minimal. The left epididymis was processed for histological analysis under light microscopy, and the right was used to assess protein expression using shotgun proteomics. Calomys tener presented higher mean values for luminal and tubular diameters than N. lasiurus in the caput region. We observed similar morphologies and relative frequencies in the epididymal epithelium of principal, basal, and clear cells in the 2 species. Shotgun proteomics detected 58 and 64 proteins in 1 or more epididymal regions of C. tener and N. lasiurus, respectively. Aldose reductase, superoxide dismutase Cu-Zn, carboxylesterase 5A, and clusterin were only detected in the epididymis of N. lasiurus. The epididymides of C. tener and N. lasiurus differed in both histomorphometry and protein expression, suggesting that describing the epididymis in closely related species may provide a complementary tool for taxonomic studies. Knowledge of epididymal histophysiology helps establish a foundation for better understanding of the reproductive biology of these rodents, and our data from a protected area create a baseline for studies investigating the effects of environmental endocrine disruptors on functionality of the epididymal epithelium.

Densidade populacional de raposa-do-campo Lycalopex vetulus (Carnivora, Canidae) em áreas de pastagem e campo sujo, Campinápolis, Mato Grosso, Brasil

In face of the growing disturbance of the Cerrado biome, due to the expansion of the agricultural borders of Central Brazil, it becomes important to evaluate the adaptation capacity of animal species to the anthropized environment. Thus, this work was developed aiming to estimate and compare the population density of hoary fox Lycalopex vetulus (Lund, 1842) in two areas of Central Brazil with distinct disturbance degrees, pasture and campo sujo, a vegetation type of Cerrado. For this, during the period of August to November 2005, nocturnal sampling were done along linear transects, totaling 129.8 km in the campo sujo and 62.08 km in the pasture. A total of 23 sightings of hoary fox was obtained in campo sujo and 52 in the pasture. Estimations of population density were made using the Distance 5.0 software, which chose the half normal + hermite adjust as the model with best fit. Population density was higher in the pasture (D=4.28 individuals/km2; IC=2.69 - 6.82) than in the campo sujo (D=1.21 individuals/km2; IC=0.73 - 2.01), what is likely related, mainly, to higher availability of food and reduction of potential predators. As its diet is composed basically of termites, especially from the genera Syntermes and Cornitermes, the hoary fox find in the pasturage area an alimentary base abundant and stable. Moreover, the environmental simplification, due to the pasture implantation, end up reducing or to local extinction potential predators of the hoary fox, such as Chrysocyon brachyurus (Illiger, 1815), supporting the increase of population density of this specie in this kind of environment. Results indicate that the Cerrado endemic hoary fox is able to survive, and even proliferate, in highly modified areas of the Cerrado.

Survey of large and medium-sized terrestrial mammals in the Serra do Brigadeiro State Park, Minas Gerais, Brazil

The aim of this study was to survey the species of large and medium-sized terrestrial mammals occurring at Serra do Brigadeiro State Park (SBSP). Data was compiled from two studies carried out in 2008. Data was collected through sand plots and camera traps. Thirteen species were recorded, one that had not been registered before ( Leopardus wiedii ) and one exotic ( Canis lupus familiaris ). Species richness estimate for camera trapping was 13.53±1.75. For the sand plots, estimate was lower (9±1.73 species). The low number of inventories focusing on large and medium-sized terrestrial mammals in the Mantiqueira region of the Atlantic forest and the presence of the domestic dogs within the Park limits emphasizes the need for monitoring programs to identify the major threats to preserved areas in the region.

Dental eruption sequence and hypsodonty index of a Pleistocene macraucheniid from the Brazilian Intertropical Region

Abstract. Litopterna is represented in the Pleistocene of the Brazilian Intertropical Region by a monospecific genus of Macraucheniidae, Xenorhinotherium. Although most of the knowledge about this family is derived from the dentition, some dental features still remain unknown. This study describes the eruption sequence of permanent dentition and classifies the hypsodonty status of X. bahiense. The specimens studied are from Toca dos Ossos, a limestone cave located in Bahia State. We perform qualitative macroscopic analysis to describe the eruption dental sequence. Additionally, we perform quantitative analysis to determine the hypsodonty index. The dental eruption sequence of the juvenile specimen is M1, M2, I1, I2, M3, I3, P1, P2, P3, and P4. In addition, the analysis of tooth wear in adult specimens provides similar results. The hypsodonty index assigns a mesodont tooth crown for X. bahiense. The dental eruption sequence is most similar to a rapid-growth extant mammal. Moreover, our results do not support afrotherian-like delayed dental eruption to Litopterna. The hypsodonty index can be related to data on vegetation of the Brazilian Intertropical Region and the shape of the premaxilla of X. bahiense, both of which suggest a browsing diet for this macraucheniid.

Bats (Mammalia: Chiroptera) of Mata do Paraíso research station, Viçosa, Minas Gerais, Brazil

The aim of this study was to document the records of bat species collected at the Estacao de Pesquisa Treinamento e Educacao Ambiental (EPTEA) da Mata do Paraiso, a small fragment of Atlantic Rainforest of 200 ha in Vicosa, Minas Gerais, Brazil. Original data was obtained by capture sessions with mist nets from November 2007 to October 2008, and complemented with material from the collection database of Museu de Zoologia Joao Moojen, Universidade Federal de Vicosa. We found a total of 17 bat species distributed in five families at the EPTEA Mata do Paraiso.