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We assessed the evolutionary histories of two hummingbirds, Augastes scutatus and Augastes lumachella, endemic to the highlands of the Espinhaço Range in Brazil. These hummingbirds are considered relictual taxa with phylogenetic affinities to members of the genus Schistes from the Andean region. We reconstructed phylogenetic relationships of Augastes through the use of mitochondrial DNA and nuclear sequences within the Polytminae hummingbird clade, and found that the inferred phylogenetic reconstructions placed A. scutatus as the sister species of A. lumachella and Augastes as sister to Schistes geoffroyi from the northern Andes, as previously suggested by similarities found in plumage and morphology. Our results are consistent with an initial divergence of Augastes and Schistes lineages in the Late Miocene, associated with geological and climatic changes across the South American landscape. A Late Pliocene vicariant event between A. scutatus and A. lumachella may be associated with climatically distinct environmental conditions influencing the local differentiation and adaptation of ancestral Augastes populations. Our findings represent additional important evidence of vicariant events between east and west in southern South America, and between north and south within the Espinhaço Range of Brazil. [ABSTRACT FROM AUTHOR]

In this study, we verified the power of DNA barcodes to discriminate Neotropical birds using Bayesian tree reconstructions of a total of 7404 COI sequences from 1521 species, including 55 Brazilian species with no previous barcode data. We found that 10.4% of species were nonmonophyletic, most likely due to inaccurate taxonomy, incomplete lineage sorting or hybridization. At least 0.5% of the sequences (2.5% of the sampled species) retrieved from GenBank were associated with database errors (poor-quality sequences, Nu MTs, misidentification or unnoticed hybridization). Paraphyletic species (5.8% of the total) can be related to rapid speciation events leading to nonreciprocal monophyly between recently diverged sister species, or to absence of synapomorphies in the small COI region analysed. We also performed two series of genetic distance calculations under the K2P model for intraspecific and interspecific comparisons: the first included all COI sequences, and the second included only monophyletic taxa observed in the Bayesian trees. As expected, the mean and median pairwise distances were smaller for intraspecific than for interspecific comparisons. However, there was no precise 'barcode gap', which was shown to be larger in the monophyletic taxon data set than for the data from all species, as expected. Our results indicated that although database errors may explain some of the difficulties in the species discrimination of Neotropical birds, distance-based barcode assignment may also be compromised because of the high diversity of bird species and more complex speciation events in the Neotropics. [ABSTRACT FROM AUTHOR]

We describe Cinclodes espinhacensis (Furnariidae) , a new species discovered at high elevation in the southern portion of the Espinhaço Range, in the state of Minas Gerais, southeastern Brazil. This new taxon is closely related to the Long-tailed Cinclodes Cinclodes pabsti, endemic to Serra Geral, southern Brazil. We present diagnostic morphological, genetic and vocal characters that support the rank of species for this allopatric taxon. It is readily distinguishable from C. pabsti by its much darker back, chest and flanks, lower body mass, shorter tarsus-length, lower frequency of vocalizations, and longer duration of calls. DNA sequence data estimate that the divergence time between this new species and Cinclodes pabsti occurred c. 220 000 years ago, during the late Pleistocene. This discovery illustrates remarkable biogeographical connections among the cold regions of South America. The new species has a restricted range and we suggest it meets the criteria of the IUCN Red List category of Endangered. [ABSTRACT FROM AUTHOR]

Premise of the study: Microsatellite primers were developed for the first time in Velloziaceae, in the endangered species Vellozia gigantea. Methods and Results: Using two different protocols, seven primer sets were characterized in three populations of V. gigantea. The primers amplified di- and trinucleotide repeats with six to 12 alleles per locus. These revealed high levels of genetic variation, presenting an average observed heterozygosity of 0.508 in V. gigantea. The seven primers were tested for cross-amplification in three Vellozia species. All primers successfully amplified in V. auriculata. Six primers amplified in V. compacta and three in V. hirsuta. Conclusions: The new marker set described here will be useful for studies of population genetics of V. gigantea. The cross-amplification results indicate the utility of primers for studies in other Vellozia species. [ABSTRACT FROM AUTHOR]