First record of Pterygodermatites (Pterygodermatites) (Nematoda: Rictulariidae) in South America, with the description of a new species from the Atlantic Forest, southeast Brazil.

Pterygodermatites are parasitic nematodes found in mammals worldwide, except Australia. There are 38 described species, which are found parasitizing bats, rodents, marsupials, carnivores and primates. We present taxonomic notes on nematodes collected from the digestive tract of bats from the Atlantic Forest in southeast Brazil. Two species previously recorded in marsupials in this region, Pterygodermatites (Paucipectines) elegans and Pterygodermatites (Paucipectines) jagerskioldi, were found parasitizing molossid and vespertilionid bats, respectively. A new species Pterygodermatites (Pterygodermatites) atlanticaensis found in phyllostomid bats is here described. Despite earlier work based on females, taxonomic work on this group of nematodes is usually based on male characters, such as position and number of caudal papillae, which is a problem because males are short-lived and not easily found. Here we also describe in detail female characters, such as position of the last pair of cuticular processes relative to the posterior end. This is the first record of P. (Pterygodermatites) in South America and the first record of P. (Paucipectines) jagerskioldi in bats.

Historical connections among river basins and climatic changes explain the biogeographic history of a water rat.

BACKGROUND: The water rat Nectomys squamipes (Cricetidae: Sigmodontinae) is a semiaquatic rodent from eastern South America that shows shallow genetic structure across space, according to some studies. We tested the influence of hydrography and climatic changes on the genetic and phylogeographic structure of this semiaquatic small mammal. METHODS: DNA sequences of two mitochondrial genetic markers (Cyt b and D-loop) and six microsatellite loci from water rats were collected at 50 localities in five river basins in the Atlantic Forest along the eastern coast of South America. We evaluated the genetic structure within and among river basins, and we estimated divergence dates. Species distribution models for the present and past were built to identify possible gene flow paths. RESULTS: Mitochondrial data and species distribution models showed coherent results. Microsatellite loci showed a more complex pattern of genetic differentiation. The diversification of N. squamipes haplotypes occurred during the Pleistocene and the river basin cannot explain most of the genetic structure. We found evidence of population expansion during the last glacial maximum, and gene flow paths indicate historical connections among rivers in the Atlantic Forest. DISCUSSION: Historical connections among rivers in the Atlantic Forest may have allowed N. squamipes to disperse farther across and within basins, leading to shallow genetic structure. Population expansions and gene flow through the emerged continental shelf during glacial period support the Atlantis forest hypothesis, thus challenging the forest refuge hypothesis.

High Trypanosoma spp. diversity is maintained by bats and triatomines in Espírito Santo state, Brazil.

The aim of this study was to reevaluate the ecology of an area in the Atlantic Forest, southeast Brazil, where Chagas disease (CD) has been found to occur. In a previous study, immediately after the occurrence of a CD case, we did not observe any sylvatic small mammals or dogs with Trypanosoma cruzi cruzi infections, but Triatoma vitticeps presented high T. c. cruzi infection rates. In this study, we investigated bats together with non-volant mammals, dogs, and triatomines to explore other possible T. c. cruzi reservoirs/hosts in the area. Seventy-three non-volant mammals and 186 bats were captured at three sites within the Guarapari municipality, Espírito Santo state. Rio da Prata and Amarelos sites exhibited greater richness in terms of non-volant mammals and bats species, respectively. The marsupial Metachirus nudicaudatus, the rodent Trinomys paratus, and the bats Artibeus lituratus and Carollia perspicillata were the most frequently captured species. As determined by positive hemocultures, only two non-volant mammals were found to be infected by Trypanosoma species: Monodelphis americana, which was infected by T. cascavelli, T. dionisii and Trypanosoma sp., and Callithrix geoffroyi, which was infected by T. minasense. Bats presented T. c. cruzi TcI and TcIII/V, T. c. marinkellei, T. dionisii, T. rangeli B and D, and Trypanosoma sp. infections. Seven dogs were infected with T. cruzi based only on serological exams. The triatomines T. vitticeps and Panstrongylus geniculatus were found to be infected by trypanosomes via microscopy. According to molecular characterization, T. vitticeps specimens were infected with T. c. cruzi TcI, TcII, TcIII/V, and TcIV, T. c. marinkellei and T. dionisii. We observed high trypanosome diversity in a small and fragmented region of the Atlantic Forest. This diversity was primarily maintained by bats and T. vitticeps. Our findings show that the host specificity of the Trypanosoma genus should be thoroughly reviewed. In addition, our data show that CD cases can occur without an enzootic cycle near residential areas.

Seasonal flooding regime and ecological traits influence genetic structure of two small rodents.

Although codistributed species are affected by the same abiotic factors, such as rivers and seasonal flooding regimes, ecological traits, such as locomotion habits and habitat preferences, may also influence differences in levels of genetic diversity and differentiation. We examined population genetic structure and diversity of Hylaeamys megacephalus and Oecomys aff. roberti, two cricetid rodent species from the mid-Araguaia River in central Brazil, using mitochondrial DNA sequence data. Specifically, we aim to test whether the Araguaia River acts as a barrier to the gene flow of these two species and to assess how ecological traits, such as locomotion habits and habitat preferences, may influence differences in levels of genetic diversity and differentiation. As both species occur in flooded forests, neither showed genetic differences related to river banks. Oecomys aff. roberti showed stronger population structure that appears to be associated with isolation by distance. This arboreal species maintained stable populations in the Araguaia River, while the terrestrial H. megacephalus was more affected by seasonal floods, resulting in a genetic signature of population expansion. Our initial predictions were largely supported by our results given that locomotion habits and habitat preferences of each species appears to have played a role on the genetic structure of these two sympatric rodent species.

Highly conserved d-loop sequences in woolly mouse opossums Marmosa (Micoureus).

This study reports the occurrence of highly conserved d-loop sequences in the mitochondrial genome of the woolly mouse opossum genus Marmosa subgenus Micoureus (Mammalia, Didelphimorphia, Didelphidae). Sixty-six sequences of Marmosa (Micoureus) demerarae, Marmosa (Micoureus) constantiae, and Marmosa (Micoureus) paraguayanus were amplified using universal d-loop primers and virtually no genetic differences were detected within and among species. These sequences matched the control region of the mitochondrial marsupial genome. Analyses of qualitative aspects of these sequences revealed that their structural composition is very similar to the d-loop region of other didelphid species. However, the total lack of variability has not been reported from other closely related species. The data analyzed here support the occurrence of highly conserved d-loop sequences, and we found no support for the hypothesis that these sequences are d-loop-like nuclear pseudogenes. Furthermore, the control and flanking regions obtained with different primers corroborate the lack of variability of the d-loop sequences in the mitochondrial genome of Marmosa (Micoureus).

Non-volant tetrapods from Reserva Biológica de Duas Bocas, State of Espírito Santo, Southeastern Brazil

Reserva Biológica de Duas Bocas (2,910 ha) is one of the largest Atlantic forest remnants in the State of Espírito Santo, Southeastern Brazil. We recorded non-volant tetrapods in this area from May 2007 through April 2008, using pitfalls, live traps, camera traps, and diurnal and nocturnal opportunistic searches. In addition, we compiled available museum and literature records from this area. We documented 52 species of amphibians, 24 species of non-avian reptiles, and 39 species of non-volant mammals. Out of these 115 species, 47 are new records for this area and six other species had their geographic ranges expanded with the present study. Furthermore, we present the record of predation of the tree frog Hypsiboas faber by the snake Chironius bicarinatus. Out of the species listed, five species are listed as threatened with extinction in the State of Espírito Santo, and many others have uncertain conservation status. Reserva Biológica de Duas Bocas is an important wildlife refuge, especially considering the expansion of urban areas in its surroundings.

A Reserva Biológica de Duas Bocas (2.190 ha) é um dos maiores remanescentes de Mata Atlântica do Estado do Espírito Santo, Sudeste do Brasil. Nós amostramos tetrápodes não voadores nessa área entre maio de 2007 e abril de 2008, utilizando armadilhas de queda, armadilhas de isca, armadilhas fotográficas e buscas oportunísticas diurnas e noturnas. Além disso, nós compilamos registros de vertebrados não voadores ocorrentes nesta área disponíveis na literatura e através de espécimes em museus. Nós documentamos 52 espécies de anfíbios, 24 espécies de répteis não voadores e 39 espécies de mamíferos não voadores. Do total de 115 espécies, 47 configuram novos registros para a área e seis outras espécies tiveram sua distribuição geográfica ampliada com os resultados do presente estudo. Além disso, apresentamos o registro de predação da perereca Hypsiboas faber pela serpente Chironius bicarinatus. Cinco das espécies registradas são listadas como ameaçadas no Estado do Espírito Santo e muitas outras possuem estado de conservação incerto. A Reserva Biológica de Duas Bocas é um importante refúgio de vida selvagem, principalmente quando consideramos a expansão de áreas urbanas no seu entorno.

Pequenos mamíferos não voadores em fragmentos de Mata Atlântica e áreas agrícolas em Viana, Espírito Santo, Brasil / Non-flying small mammals in Atlantic Forest fragments and agricultural lands in Viana, state of Espírito Santo, Brazil

Nós inventariamos os pequenos mamíferos não-voadores em Viana, Espírito Santo, sudeste do Brasil, em 1981-1982 e 2006-2007. Foram capturados 439 pequenos mamíferos não-voadores pertencentes a três ordens (Didelphimorphia, Rodentia e Lagomorpha) e seis famílias (Didelphidae, Sciuridade, Cricetidae, Muridae, Echimyidae e Leporidae). As espécies mais abundantes foram os roedores Akodon cursor e Nectomys squamipes e o marsupial Metachirus nudicaudatus. Registramos pela primeira vez a ocorrência do roedor equimídeo Euryzygomatomys spinosus no estado do Espírito Santo. A riqueza específica (S = 21) e o índice de diversidade de Shannon (H = 2,23) estão entre os maiores registrados para pequenos mamíferos da Mata Atlântica no estado, mesmo quando comparados aos valores obtidos para unidades de conservação. Esses maiores valores de riqueza e diversidade encontrados estão provavelmente associados à heterogeneidade de hábitat e evidenciam a necessidade de conservação dos fragmentos florestais de Viana, os quais são importantes depositários da biodiversidade da Mata Atlântica.

We surveyed non-flying small mammals at Viana, Espírito Santo, southeastern Brazil, in 1981-1982 and 2006-2007. We trapped 439 non-flying small mammals belonging to three orders (Didelphimorphia, Rodentia, and Lagomorpha) and six families (Didelphidae, Sciuridade, Cricetidae, Muridae, Echimyidae, and Leporidae). The most abundant species were the rodents Akodon cursor and Nectomys squamipes and the marsupial Metachirus nudicaudatus. We recorded the echimyid rodent Euryzygomatomys spinosus for the first time in the state of Espírito Santo. The species richness (S = 21) and Shannon diversity index (H = 2.23) are among the highest recorded for Atlantic Forest small mammals in the state, even when compared to values from protected areas. These higher richness and diversity values are probably related to habitat heterogeneity and highlight the need for conservation of Viana's forest fragments, which are an important source of Atlantic Forest biodiversity.