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A broad panel of tens of thousands of microsatellite loci is unveiled for an endangered piracema (i.e. migratory) South American fish, Brycon orbignyanus. Once one of the main fisheries resources in the Platine Basin, it is now almost extinct in nature and focus of intense aquaculture activity. A total of 178.2 million paired-end reads (90 bases long) were obtained through the use of sequencing-by-synthesis (from a primary genomic library of 500 bp DNA fragments) and is made available through NCBI's Sequence Read Archive, SRA accession SRX3350440. Short reads were assembled de novo and screening for perfect microsatellite motifs revealed more than 81 thousands unique microsatellite loci, for which primer pairs were proposed. A total of 29 polymorphic microsatellite markers were already previously validated for this panel. A partial genomic assembly is hereby presented and these genomic resources are publicly made available. These data will foster the rapid development of hundreds of new DNA markers for genetic diversity studies, conservation initiatives and management practices for this important and depleted species. The availability of such preliminary genomic data will also be of use in the areas of bioinformatics, ecology, genetics and evolution.

Bokermmanohyla saxicola is endemic to the Espinhaco Mountain Range (southeastern Brazil), and broadly distributed in montane meadows of the Serra do Cipo. Four microsatellite regions were located through genomic library screening for this frog, two of which were chosen for population structure analyses given their high variability levels (10–11 alleles assayed in 75 tadpoles from five different streams). Overall Fst was 0.056, and the studied demes fitted isolation by distance model expectations, but the increase of Fst values was unrelated to increases in geographic distance, as it would be expected in drift-gene flow equilibrium conditions. Microsatellite markers revealed lack of pairwise genetic differentiation in spatially close demes and also in some distant ones, a pattern that may be caused by the combination of limited migration ability and past event effects contingent upon suitable habitat conditions for frog movement.

The cursor complex is a group within the Akodon genus of South American rodents, formed by Akodon cursor and A. montensis. Correct distinction between these two species is of great importance since they can harbor different Hantavirus strains. These species are only distinguishable by means of karyotypic or internal anatomic features, requiring dissection; recently, some other genetic methods have become available. We developed RAPD markers capable of distinguishing between A. cursor and A. montensis. Samples included 42 individuals of A. cursor from four localities and 16 individuals of A. montensis from two localities. Fifty-five bands, 41 of which were polymorphic, were analyzed. A principal component analysis showed that this set of markers could successfully distinguish between the two species, mainly based on three RAPD bands. The number of bands in each population was compared within a 95% confidence interval as a measure of intraspecific variability. The A. cursor populations were found to have marked genetic structure across the study area (AMOVA; F(ST )= 0.21), which in part might be because of the relatively limited dispersal capabilities of this species. Species-specific bands, with potential for species identification, were identified.