ABSTRACT
Given the substantial lacunas in the understanding of the occurrence and distribution of bat species in the eastern portion of the Brazilian state of Mato Grosso (Araguaia basin), this study presents an inventory of the species known to occur in the region, highlighting the areas sampled adequately and the species known to occur in conservation units. Georeferenced records of the occurrence of bat species in the region were obtained from published studies, scientific collections, through either the SpeciesLink network or directly from the curator, as well as the capture of specimens by our research group between 2008 and 2013. A 0.5° x 0.5° (latitude/longitude) grid was added to the map of the region for the quantification of the bat species richness of each grid cell. A total of 63 chiropteran species were recorded for the study area. Only 10 of the 30 grid cells had records of bats, and just three contained more than 20 species, and were considered to be sampled adequately on a minimal level. Bat species have been recorded in three conservation units, two state and one municipal. The number of species recorded represents 82.7% of the total of chiropterans known to occur in Mato Grosso, although 12 species were recorded in the state for the first time, reinforcing the paucity of data available on the distribution of bats in the region. The high bat species richness recorded in the present study reinforces the importance of eastern Mato Grosso, a transition zone between the Amazon forest and the Cerrado savanna of central Brazil, for the conservation of Neotropical chiropterans.
Frente è lacuna existente sobre a real ocorrência e distribuição das espécies de morcegos objetivamos listar as espécies registradas na região leste do estado de Mato Grosso, Brasil, apontando os locais minimamente amostrados e as espécies catalogadas dentro das Unidades de Conservação. Foram consideradas espécies com registros georrefenciados para a região disponibilizados por periódicos científicos, coleções científicas, por meio do sistema SpeciesLink ou disponibilizados diretamente pela curadoria, além de capturas realizadas entre 2008 e 2013 pelo nosso grupo de pesquisa. Ao mapa da região leste do estado foi incorporado células de 0,5° latitudinais X 0,5° longitudinais e quantificadas sobre a riqueza de espécies de morcegos em cada célula. Foram registradas 63 espécies para a região. Das 30 células geradas 10 tiveram pelo menos uma espécie registrada e três tiveram mais de 20 espécies sendo consideradas minimamente amostradas. Três Unidades de Conservação tiveram espécies catalogadas, sendo duas estaduais e uma municipal. A região leste teve o registro de 82,7% do total de espécies conhecidas para o estado de Mato Grosso, sendo que 12 ainda não haviam sido assinaladas para o estado demonstrando que ainda pouco se conhece sobre a real distribuição dos morcegos na região. Considerando a alta riqueza encontrada enfatizamos a importância da região leste de Mato Grosso, zona de transição entre Cerrado e Amazônia, e também o potencial do estado na conservação dos morcegos neotropicais.
ABSTRACT
In the state of Mato Grosso, studies aiming to investigate the diversity and richness of bats are still scarce. In the present study, the chiropteran fauna of eastern Mato Grosso (Brazil) was investigated at four sites representing the Cerrado savanna biome with different degrees of anthropogenic impact, in the municipality of Nova Xavantina. Surveys were conducted between January and December, 2010, with a total of 48 nights of mist-netting. A total of 423 bats were captured, representing 25 species distributed in five families. A greater abundance of individuals was recorded at all sites during the rainy season, with considerable variation being observed over the course of the year in species richness and composition, and the abundance of bats. Species richness and bat abundance were higher in the better preserved habitats in comparison with the impacted areas. The timing of foraging activities appeared to vary among the specimens and there was a progressive increase in activity until 19:30 h, with a marked decline after 22:30 h. The ecological diversity (Shannon-Wiener index) of the bat community within the study area was H′ = 2.37.
No estado de Mato Grosso, os estudos visando investigar a diversidade e riqueza de morcegos ainda são escassos. Neste estudo, a quiropterofauna da região leste mato-grossense foi investigada por meio de capturas em quatro áreas remanescentes de Cerrado com diferentes índices de conservação, no município de Nova Xavantina. As capturas ocorreram de janeiro a dezembro de 2010, totalizando 48 noites de amostragem. Foram capturados 423 indivíduos, distribuídos em 25 espécies e cinco famílias. Os quatro ambientes apresentaram maior abundância na estação chuvosa e, ao longo dos meses e entre as estações do ano a composição, riqueza e abundância de morcegos variaram. As áreas mais preservadas apresentaram maior riqueza e maior abundância de morcegos em relação às áreas degradadas. Foi possível verificar que o horário de forrageamento variou entre os espécimes capturados, ocorrendo um pico crescente de atividade até às 19:30h e uma redução acentuada por volta das 22:30h. A diversidade calculada pelo índice de Shannon-Wiener (H′) para as áreas foi de H′=2,37.
ABSTRACT
The purpose of this work was to verify the ability of the enzyme Alu I to cleave and/or remove satellite DNA sequences from heterochromatic regions in chromosomes of bats, by identifying the occurrence of modifications in the pattern of fluorescence in situ hybridization with telomeric DNA. The localization and fluorescence intensity of the telomeric DNA sites of the Alu-digested and undigested chromosomes of species Eumops glaucinus, Carollia perspicillata, and Platyrrhinus lineatus were analyzed. Telomeric sequences were detected at the termini of chromosomes of all three species, although, in C. perspicillata, the signals were very faint or absent in most chromosomes. This finding was interpreted as being due to a reduced number of copies of the telomeric repeat, resulting from extensive telomeric association and/or rearrangements undergone by the chromosomes of Carollia. Fluorescent signals were also observed in centromeric and pericentromeric regions in several two-arm chromosomes of E. glaucinus and C. perspicillata. In E. glaucinus and P. lineatus, some interstitial and terminal telomeric sites were observed to be in association with regions of constitutive heterochromatin and ribosomal DNA (NORs). After digestion, these telomeric sites showed a significant decrease in signal intensity, indicating that enzyme Alu I cleaves and/or removes part of the satellite DNA present in these regions. These results suggest that the telomeric sequence is a component of the heterochromatin, and that the C-band- positive regions of bat chromosomes have a different DNA composition