Phylogenetic relationships of tyrant-flycatchers (Aves: Tyrannidae), with an emphasis on the elaeniine assemblage.

The tyrant-flycatchers (Tyrannidae) are arguably the largest avian family in the Western Hemisphere with approximately 100 genera and 430 species. Although the composition of the family is largely settled, intergeneric relationships are poorly understood. Morphological and behavior-based classifications are in disagreement with DNA-DNA hybridization data, and both have recently been contradicted by DNA-sequence studies. However, previous DNA-sequence sampling has mostly focused on two out of the six traditional tribes. In this study, we have sampled mitochondrial and nuclear sequences of additional tyrannid genera from across the Tyrannidae, with particularly dense coverage of a third tribe (Elaeniini). Our data corroborate previous DNA-sequence studies that demonstrate a basal division of Tyrannidae into a pipromorphine group (recruited from two morphological tribes) and the core Tyrannidae. Furthermore, we identify a new assemblage that includes Platyrinchus and the enigmatic Neopipo, although the position of this lineage within the Tyrannidae remains incertae sedis. Within the core Tyrannidae, we find strong support for a monophyletic elaeniine assemblage, and discuss a number of strongly supported sub-clades and species-level arrangements that display varying levels of agreement with previous classifications. The elaeniine assemblage may be the sister group to all other core Tyrannidae, and it is in virtually complete congruence with a previous classificatory scheme based on syringeal morphology.