Species inventories are important tools to evaluate biodiversity losses and contribute to the conservation of endangered areas. The Amazon and Cerrado are the largest Brazilian biomes and represent some of the most threatened regions of the country. Due to its location between these biomes, the state of Maranhão, Northeast Brazil, possesses a great variety of habitats and a high local diversity. Nonetheless, few faunistic inventories of diversified groups have been performed in the state. In the specific case of butterflies, a well-known biological indicator, no inventories have been published in the past years. This study aimed to expand the knowledge on the composition of butterflies in Amazon and Cerrado remnants of Maranhão. Butterflies were sampled between 2011 and 2015 across eight municipalities of the state. Captures were made through entomological nets and baited traps. In total, 189 species were sampled, of which 165 were captured in the Amazon, 65 in the Cerrado and 41 in both biomes. We sampled 167 species through entomological nets and 43 through baited traps, representing 12% of similarity in species composition between sampling methods. We estimate that the recorded species represent a small subset of the butterflies from Maranhão. Therefore, long-term researches in poorly studied areas of the state are recommended to identify novel and/or endemic taxa.Keywords: tropical forest, diversity, Lepidoptera, Neotropical region, savanna. Borboletas de remanescentes de Amazônia e Cerrado do Maranhão, nordeste do BrasilResumo: Inventários de espécies são ferramentas importantes para avaliar perdas de biodiversidade e contribuir para a conservação de áreas ameaçadas. A Amazônia e o Cerrado são os maiores biomas brasileiros e representam algumas das regiões mais ameaçadas do país. Devido à sua localização entre estes biomas, o estado do Maranhão, nordeste do Brasil, possui uma grande variedade de habitats e uma alta diversidade local. No entanto, poucos inventários faunísticos de grupos diversificados foram realizados no estado. No caso específico de borboletas, um indicador biológico bem conhecido, nenhum inventário foi publicado nos últimos anos. Este estudo objetivou expandir o conhecimento sobre a composição de borboletas de remanescentes de Amazônia e Cerrado do Maranhão. As borboletas foram amostradas entre 2011 e 2015 em oito municípios do estado. As capturas foram realizadas através de redes entomológicas e armadilhas com iscas. No total, 189 espécies foram amostradas, das quais 165 foram capturadas na Amazônia, 65 no Cerrado e 41 em ambos os biomas. Nós amostramos 167 espécies através de redes entomológicas e 43 através de armadilhas com iscas, representando 12% de similaridade na composição de espécies entre métodos de amostragem. Nós estimamos que as espécies registradas representam um pequeno subconjunto das borboletas do Maranhão. Deste modo, pesquisas de longa duração em áreas pouco estudadas do estado são recomendadas para identificar taxa novos e/ou endêmicos.

Updated distribution ranges are crucial for conservation status assessments. Comprehensive analyses combining published literature and available data on historical catches and species distribution models (SDMs) are effective tools that could improve the prediction of more realistic scenarios for some species, especially those with limited information available and facing multiple threats. The present study aimed at generating an updated distribution for the smalltail shark Carcharhinus porosus, one of the most threatened and understudied shark species of the western Atlantic Ocean. Estimates of the key areas for this species conservation based on the SDMs, and trends in catch probabilities throughout its distribution range are provided. Four algorithms (BIOCLIM, Domain, Mahalanobis, and Maximum Entropy) were used to model the distribution of C. porosus and calculate its habitat suitability based on marine environmental variables. To assess historical catch probability trends, we built a generalized linear model from published and grey literature data. This analysis was used to estimate catch probability as an indication of population trends. SDMs suggest that the northern coast of South America (NCSA) harbours the most suitable habitats for C. porosus in the world, which was expected given its historically high catch rate in this region. In addition, there was a continuously declining catch probability trend starting in the 1970s. However, the decline was smaller for the NCSA as compared with the Gulf of Mexico and the eastern South America coast. Results indicate that the NCSA should be considered the currently most important area in the world for this species conservation. Furthermore, the lack of data throughout Central and South American marine regions hampers the evaluation of extinction risk throughout its updated distribution. Thus, research in these areas is urgently required for a more comprehensive conservation status assessment.

Deforestation has negative impacts on diversity and community patterns of several taxa. In the eastern Amazon

Species interactions can propagate disturbances across space via direct and indirect effects, potentially connecting species at a global scale. However, ecological and biogeographic boundaries may mitigate this spread by demarcating the limits of ecological networks. We tested whether large-scale ecological boundaries (ecoregions and biomes) and human disturbance gradients increase dissimilarity among plant-frugivore networks, while accounting for background spatial and elevational gradients and differences in network sampling. We assessed network dissimilarity patterns over a broad spatial scale, using 196 quantitative avian frugivory networks (encompassing 1496 plant and 1004 bird species) distributed across 67 ecoregions, 11 biomes, and 6 continents. We show that dissimilarities in species and interaction composition, but not network structure, are greater across ecoregion and biome boundaries and along different levels of human disturbance. Our findings indicate that biogeographic boundaries delineate the world’s biodiversity of interactions and likely contribute to mitigating the propagation of disturbances at large spatial scales.