The interspecific limits of the polytypic specie Deconychura longicauda (Dendrocolaptidae) were investigated by a combined analysis including molecular, morphological, and vocal characters. A total of 1,108 base pairs of mitochondrial genes Cyt b and ND2 were used to build phylogenetic hypotheses, whereas the morphological and vocal characters were analyzed with univariate and multivariate statistical methods. All recovered trees indicated high levels of genetic differentiation and phylogeographic structure in Deconychura longicauda, with the recognition of four major groups well-supported statistically and geographically consisting of birds from (1) the Guiana area of endemism in northeastern South America, (2) the Amazon basin excluding the Guianan shield, (3) the eastern slope of the Andes and (4) trans-Andean South America and Central America. The levels of genetic divergence between these clades reach 6-8% (among birds from Guianan, non-Guianan, eastern slope of the Andes and, trans-Andean birds). Although morphological characters contribute little to the diagnoses among Deconychura, loudsongs, consistently distinguish them. Based on those analyzes, we recommend the splitting of D. longicauda into the following phylogenetic and biological species based on their molecular and vocal unequivocal diagnoses: Deconychura longicauda, D. pallida, D. zimmeri, D. connectens, D. typica and one yet unnamed taxon endemic to the eastern slope of the Andes.
|
