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Paraguay, situated in south-central South America, lies at the nexus of several major biomes, and exhibits high species richness for a relatively small country. Nevertheless, that faunal diversity is poorly known, and new species for the country continue to come to light. This paper reports on 3 species of rodents, 1 new for the country and 2 known previously in Paraguay from 1 specimen. We emphasize the need for more and better training of new field and museum biologists, as well as for directors of permitting agencies and protected areas. [ABSTRACT FROM AUTHOR]

A new species, Androlaelaps delomys n. sp., (Acari: Mesostigmata: Laelapidae) is described from the sigmodontine rodent, Delomys dorsalis, collected in the Boraceia Biological Station in the state of Sao Paulo, Brazil. This mite is associated with the endemic rodent genus Delomys throughout the Atlantic Forest region of southeastern Brazil. [ABSTRACT FROM AUTHOR]

Abstract: Quantitative real-time RT-PCR (qRT-PCR) is a sensitive technique for gene expression analysis. A critical factor for creating reliable data in relative quantification is the normalization of the expression data of genes of interest. Therefore the needed normalization factor is calculated out of the expression data of co-amplified genes that are stable expressed in the certain sample material, the so-called reference genes. In this study, we demonstrate the important process of validating potential reference genes using a non-model species. As there are almost no sequences known of the Pallid Atlantic Forest Rat (Delomys sublineatus), a rodent used as indicator species in conservation studies of the endangered Brazilian rainforest, suitable primer sets are more problematic to find than in model species. Out of nine tested primer sets designed for the fully sequenced Mus musculus, five could be used for the establishment of a proper running SYBR-Green assay and validation of their constant expression. qRT-PCR results of 12 cDNAs of Delomys livers were analyzed with three different validation software programs: BestKeeper, NormFinder and geNorm. Our approach showed that out of the five (Sdha, Canx, Pgk1, Actb and Actg1) potential reference genes, the first four should be used for accurate normalization in further relative quantification analyses. Transferring data from close-by model organisms makes high sensitive real-time RT-PCR applicable even to free-ranging non-model organisms. Our approach might be suitable for other non-model organisms. [Copyright &y& Elsevier]

We investigated the population density of the two common rodent species Akodon montensis, Oligoryzomys nigripes, and the more specialized endemic Delomys sublineatus in secondary forest fragments of the highly endangered coastal Atlantic Rainforest. Linear regression was used to examine relationships between population density and four landscape variables. We tested the hypothesis that rare species, which are more affected by fragmentation than the common species, should decrease in population density with decreasing fragment size while the density of common generalist species should be unaffected or increase in smaller fragments. The results revealed that A. montensis and O. nigripes showed no significant association to any landscape variable. The density of D. sublineatus showed a strong tendency to a positive correlation to fragment size as well as a negative correlation to edge density. The results underline the importance of large and connected forest remnants in the Atlantic Rainforest to guarantee an effective protection of endemic small mammal species. [ABSTRACT FROM AUTHOR]