Olivaceous Elaenia

The olivaceous elaenia (Elaenia mesoleuca) is a species of bird in subfamily Elaeniinae of family Tyrannidae, the tyrant flycatchers. It is found in Argentina, Brazil, Paraguay, and Uruguay. == Taxonomy and systematics == Though one mid-late twentieth century publication credited Lichtenstein with the species description, since the 1990s taxonomic systems attribute it to Deppe. The olivaceous elaenia is monotypic. == Description == The olivaceous elaenia is 14 to 16 cm (5.5 to 6.3 in) long and weighs 16 to 20 g (0.56 to 0.71 oz). It is a small elaenia without a crest. The sexes have the same plumage. Adults have a dull olive crown with minimal or no white in the middle. They have a white eyering. Their upperparts are dull olive. Their wings are dusky with yellowish or white tips on the coverts that show as two wing bars. Their flight feathers have narrow whitish edges. Their tail is dusky. Their throat is dull gray, their breast olive in a vest-like pattern, their belly white, and their flanks and undertail coverts whitish with a yellow wash. Both sexes have a brown iris, a black bill with a dusky pinkish base to the mandible, and black legs and feet.…