Livros e Publicações
URI permanente para esta coleçãohttps://bdc.icmbio.gov.br/handle/cecav/1481
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Item New records and distribution extension of Acanthochelys macrocephala (Rhodin, Mittermeier & McMorris 1984) in midwestern Brazil.(Cuad. herpetol., 2023) Dorado-Rodrigues, Tainá Figueras; Brito, Elizângela Silva; Silva, Karoline Rodrigues; Valadão, Rafael Martins; Cunha, Fábio Andrew Gomes; Strüssmann, ChristineItem Assessing Brazilian turtles’ vulnerability BY USING species distribution models AND dispersal constraints(Biodiversity and Conservation, 2024-01-27) Pinto, Hugo Bonfim de Arruda; Valadão, Rafael Martins; Andrade, André Felipe Alves de; Batista, Flavia Regina de Queiroz; Marco Júnior, Paulo DeMost assessments of the conservation status of Brazilian turtles use the IUCN geographic range criteria performed by the Minimum Convex Polygon (MCP). This technique often leads to over- or under-estimating the geographic distribution of rare, vulnerable, or endangered species. We aimed to demonstrate that using Species Distribution Models (SDM) on the geographic range assessment of turtles could be more accurate than using the minimum polygon convex. We reduced overestimation of species’ extent of occurrence by adding dispersal constraints, which avoids under- or over-estimating the impact of threatening events. The extent of occurrence derived from MCP was 31% higher than SDM on average, ranging from 4 to 311% higher. Using remaining habitat variables, we found that habitat loss within the predicted extent of occurrence increased by 79% from 1985 to 2019, and inferred population fragmentation increased by 161%. The distribution of turtles Acanthochelys radiolata, Acanthochelys spixii, Hydromedusa maximiliani, Hydromedusa tectifera, Mesoclemmys vanderhaegei, Phrynops williamsi, and Ranacephala hogei is severely fragmented, with most of their extent of occurrence being split into patches that are unavailable to the species persistence. Our findings highlight the importance of using SDM combined with dispersal constraints, which may further benefit from future information about the dispersal capacity of turtles. Furthermore, adding environmental layers to this combination makes it possible to discuss processes affected by habitat fragmentation, such as the fragmentation of species populations, an aspect essential to evaluate population viability and local extinctions.Item Phylogenetic analysis of chelonian hemogregarines reveals shared species among the Amazonian freshwater turtle Podocnemis spp. and provides a description of two new species of Haemogregarina.(Parasitology Research, 2022-01-21) Correa, Jamille Karina Coelho; Picelli, Amanda Maria; da Silva, Maria Regina Lucas; Valadão, Rafael Martins; Hernández-Ruz, Emil José; Viana, Lúcio AndréThis study describes two new species of the genus Haemogregarina living in the Amazonian freshwater turtles Podocnemis expansa and Podocnemis sextuberculata. Haemogregarina species isolated from P. expansa have been characterized by the presence of encapsulated, folded immature gamonts, with the parasitophorous vacuole and fragmented chromatin located in the central region. In Haemogregarina found in P. sextuberculata, curved immature gamonts were observed inside a parasitophorous vacuole, with small, slightly arched meronts with rounded nuclei, and mature gamonts with trapezoid-shaped condensed nuclei. The novel 18S rRNA sequences obtained in this study clustered within a well-supported clade composed of hemogregarines isolated from other neotropical freshwater turtles from the families Podocnemididae and Geoemydidae. The hemogregarines found in this study were compared to Haemogregarina podocnemis from Podocnemis unifilis and Haemogregarina sp. from Podocnemis expansa, based on morphological, morphometric, and molecular data. The analysis supports the new species Haemogregarina karaja sp. nov. isolated from P. expansa and Haemogregarina embaubali sp. nov. found in P. sextuberculata.Item Diversity patterns of lizard assemblages from a protected habitat mosaic in the Brazilian Cerrado savanna(Journal of Tropical Ecology, 2022-05-16) Barros, Rafael Assis; Dorado-Rodrigues, Tainá Figueras; Valadão, Rafael Martins; Strüssmann, ChristineDifferences in habitat complexity and structure can directly influence the composition, diversity, and structure of species assemblages. Measurements of functional and phylogenetic diversity complement the commonly used measurements of taxonomic diversity, elucidating the relationships between species, their traits, and their evolutionary history. In this study, we evaluated how the mosaic of open and forested formations in a federal conservation unit in the western portion of the Brazilian Cerrado savanna influences the taxonomic, functional, and phylogenetic structure of lizard assemblages. Lizards were sampled for 15 months using pitfall traps set in open and forested formations. We recorded 292 lizards distributed among 16 species from eight families, with species composition differing among the formations. Richness was greater in the assemblages from open formations, while functional diversity and phylogenetic variability were greater in those of forested formations. Lizard assemblages in open formations were functionally and phylogenetically clustered, probably as a result of environmental filters acting on species, while the assemblages from forested formations were randomly structured. Different environmental and historical mechanisms have apparently shaped the current diversity of lizards in the region. This study shows that Cerrado vegetation mosaics can promote wide variation in different aspects of the taxonomic, functional, and phylogenetic structure from the lizard assemblages.