Phylogeny and Biogeography of the Amazona Ochrocephala (Aves: Psittacidae) Complex
Abstract We present a phylogenetic analysis of relationships among members of the Amazona ochrocephala species complex of parrots, a broadly distributed group in Middle and South America that has been a “taxonomic headache.” Mitochondrial DNA sequence data are used to infer phylogenetic relationships among most of the named subspecies in the complex. Sequence-based phylogenies show that Middle American subspecies included in the analysis are reciprocally monophyletic, but subspecies described for South America do not reflect patterns of genetic variation. Samples from the lower Amazon cluster with samples collected in western Amazonia—not with samples from Colombia and Venezuela, as was predicted by subspecies classification. All subspecies of the complex are more closely related to one another than to other Amazona species, and division of the complex into three species (A. ochrocephala, A. auropalliata, and A. oratrix) is not supported by our data. Divergence-date estimates suggest that these parrots arrived in Middle America after the Panama land-bridge formed, and then expanded and diversified rapidly. As in Middle America, diversification of the group in South America occurred during the Pleistocene, possibly driven by changes in distribution of forest habitat.
