Sharp-tailed Grass Tyrant

The sharp-tailed grass tyrant or sharp-tailed tyrant (Culicivora caudacuta) is a species of bird in the family Tyrannidae, the tyrant flycatchers. It is found in Argentina, Bolivia, Brazil, Paraguay, and Uruguay. == Taxonomy and systematics == The short-tailed grass tyrant is the only member of its genus and has no subspecies. Its closest relatives are the tachuris of genus Polystictus. == Description == The sharp-tailed grass tyrant is 10 to 11 cm (3.9 to 4.3 in) long. The sexes have almost the same plumage; females are slightly smaller than males with a shorter tail. Adult males have a slightly bushy blackish crown and females a browner one. Both sexes have a wide white supercilium and a thin black line through the eye on an otherwise warm buffy brown face. Their back and rump are buffy brown with wide blackish streaks. Their wings are buffy brown with black and pale buff streaks and edges. Their tail is highly graduated. The central feathers are stiff and most feathers' webs are quickly worn away at the ends, giving the tail a resemblance to those of Synallaxis spinetails. Their chin is white and the rest of their underparts mostly pale yellowish white with a…