No abstract

Xenarthrans—anteaters, sloths, and armadillos—have essential functions for ecosystem maintenance, such as insect control and nutrient cycling, playing key roles as ecosystem engineers. Because of habitat loss and fragmentation, hunting pressure, and conflicts with domestic dogs, these species have been threatened locally, regionally, or even across their full distribution ranges. The Neotropics harbor 21 species of armadillos, 10 anteaters, and 6 sloths. Our data set includes the families Chlamyphoridae (13), Dasypodidae (7), Myrmecophagidae (3), Bradypodidae (4), and Megalonychidae (2). We have no occurrence data on Dasypus pilosus (Dasypodidae). Regarding Cyclopedidae, until recently, only one species was recognized, but new genetic studies have revealed that the group is represented by seven species. In this data paper, we compiled a total of 42,528 records of 31 species, represented by occurrence and quantitative data, totaling 24,847 unique georeferenced records. The geographic range is from the southern United States, Mexico, and Caribbean countries at the northern portion of the Neotropics, to the austral distribution in Argentina, Paraguay, Chile, and Uruguay. Regarding anteaters, Myrmecophaga tridactyla has the most records (n = 5,941), and Cyclopes sp. have the fewest (n = 240). The armadillo species with the most data is Dasypus novemcinctus (n = 11,588), and the fewest data are recorded for Calyptophractus retusus (n = 33). With regard to sloth species, Bradypus variegatus has the most records (n = 962), and Bradypus pygmaeus has the fewest (n = 12). Our main objective with Neotropical Xenarthrans is to make occurrence and quantitative data available to facilitate more ecological research, particularly if we integrate the xenarthran data with other data sets of Neotropical Series that will become available very soon (i.e., Neotropical Carnivores, Neotropical Invasive Mammals, and Neotropical Hunters and Dogs). Therefore, studies on trophic cascades, hunting pressure, habitat loss, fragmentation effects, species invasion, and climate change effects will be possible with the Neotropical Xenarthrans data set. Please cite this data paper when using its data in publications. We also request that researchers and teachers inform us of how they are using these data.

Even though the great majority of the biomass and diversity of mammals in tropical forests inhabit the canopy (Eisenberg & Thorington 1973), most knowledge of this group is based on forest-floor samples (Lowman & Moffett 1993). Studies that include trapping efforts in the canopy are becoming increasingly common (Grelle 2003, Lambertet al. 2005, Malcolm 1995, Pattonet al. 2000, Vieira & Monteiro-Filho 2003, Vosset al. 2001), but aspects on the ecology of arboreal small mammals still remain poorly understood. Many species of non-flying mammals co-occur in the canopy and, thus, are expected to use niche dimensions differently to permit coexistence (Cameronet al. 1979). Despite the difficulties of access to and in understanding the three-dimensional use of the arboreal strata by the different species (Emmons 1995), some studies have demonstrated that the differential use of the habitat (Cunha & Vieira 2002, Gentile & Fernandez 1999), of food items (Cácereset al. 2002, Santoriet al. 1995) or both (Leiteet al. 1996, Mauffrey & Catzeflis 2003), include strategies involved in the division of resources.

Habitat fragmentation reduces biodiversity and affects ecological processes that are fundamental for maintaining ecosystem services. We investigated how landscape structure-percent forest cover, patch density, percent cover by edge, perimeter-area ratio, and spatial heterogeneity-affects the diversity of mammalian carnivores at multiple extents within 22 Atlantic Forest landscapes. We hypothesized that 1) species richness of carnivores is positively related to forest cover; and 2) the occurrence of species will vary according to its sensitivity to forest loss and its preference for forest or open areas. Species richness, composition, and occurrence of mammalian carnivores were correlated with several landscape structure metrics. Due to a high correlation among the metrics, we adopted forest cover as the principal predictor variable. We compared a forest cover model to a null model using Akaike Information Criterion (AICc), and evaluated other fragmentation metrics using a redundancy analysis. Carnivore species richness was positively related to forest cover and negatively associated with other fragmentation metrics. However, the responses to landscape structure differed among species, possibly due to their differences in habitat use. Landscape configuration is an important factor influencing carnivore species composition. Forest cover can explain some, but not all, carnivore species occurrence. Our results reinforce the protection of forests as fundamental to the conservation of carnivore species and the ecological processes in which they participate.O processo de fragmentação de habitat reduz a biodiversidade e afeta processos ecológicos fundamentais para a manutenção de serviços ecossistêmicos. Nós investigamos como as métricas de estrutura da paisagem-cobertura florestal, densidade de manchas, cobertura porcentual de borda, relação perímetro-área e heterogeneidade espacial-afetam a diversidade de mamíferos carnívoros em múltiplas extensões em 22 paisagens da Mata Atlântica. Orientamo-nos pelas seguintes hipóteses: a) a riqueza de carnívoros é relacionada positivamente com a cobertura florestal; b) a ocorrência das espécies varia de acordo com a sua sensibilidade à perda de floresta e à preferência por florestas ou áreas abertas. Riqueza, composição e ocorrência de mamíferos carnívoros foram relacionadas com várias métricas da paisagem. Devido à alta correlação entre as métricas, adotamos a quantidade