Evolutionary history of the Melanopareia torquata complex (Aves: Melanopareiidae) in open and dry environments of South America

The Cerrado, the largest Neotropical savanna in South America, is rarely the subject of biogeographic studies. We proposed to re-evaluate the taxonomy of the Melanopareia torquata complex (M. t. torquata, M. t. rufescens and M. bitorquata) to use it as a model for understanding the patterns of Neotropical savanna diversification. We used sequences from 80 specimens from 35 localities for the ND2 gene, with subsets for Cyt b, ODC and G3PDH genes. Phylogenetic reconstructions indicated the genus Melanopareia composed by sister relationship between M. elegans and M. marononica, and between M. maximiliani and M. bitorquata plus M. torquata, with sister relationship also within these last clades. We found three main clades in the M. torquata complex, with the M. bitorquata species strongly supported as the clade sister of M. t. torquata and M. t. rufescens, with low Bayesian support. Molecular dates indicated divergence between M. maximiliani and M. torquata complex in the Middle Miocene (~ 9.86 Mya) and diversification of the current lineages (three main clades) in the Plioceono-Pleistocene transition (~ 2.5 Mya). Analyses with Network 4.6 and Geneland found high genetic diversity and strong geographic structuring in each of the three taxa. Our results show that the diversification of the Melanopareiidae provides a scenario for understanding the evolution of the dry and open environments of South America, with temporal and spatial patterns apparently influenced by independent events such as the Andean uplift and the marine introgressions of the Miocene influencing genus speciation; and the arid diagonal formation and quaternary climatic oscillations influencing the diversification within the M. torquata complex.