About Culicivora caudacuta (Vieillot, 1818)
Description: The sharp-tailed grass tyrant, Culicivora caudacuta, measures 10 to 11 cm (3.9 to 4.3 in) in length. The sexes have nearly identical plumage, though females are slightly smaller than males and have a shorter tail. Adult males have a lightly bushy blackish crown, while adult females have a browner crown. Both sexes have a broad white supercilium, a thin black line running through the eye, and an otherwise warm buffy brown face. Their back and rump are buffy brown with broad blackish streaks. Their wings are buffy brown with black and pale buff streaks and feather edges. Their tail is strongly graduated; the central tail feathers are stiff, and the feather webs of most tail feathers wear away quickly at their tips, resulting in a tail shape similar to that of Synallaxis spinetails. Their chin is white, and the rest of their underparts are mostly pale yellowish white with a warm cinnamon-buff wash on the flanks. Juveniles are overall more buffy than adults. Both sexes have a dark brown iris, a black bill, and black legs and feet. Distribution and habitat: Most of the sharp-tailed grass tyrant's range lies within Brazil, in a region roughly bounded by southern Mato Grosso, southern Tocantins, and far northern Santa Catarina. Its range extends west into central Bolivia as far as La Paz Department, and southwest through eastern Paraguay into northern Argentina as far as the provinces of Santa Fe and Entre Ríos, with a small extension into Uruguay. The species has a rather local distribution across its entire range. It lives in grassland habitats including cerrado, savanna, and wettish tall native grasslands, and is often found near marshes and small watercourses. It avoids disturbed areas. Its elevation range extends from near sea level to 1,400 m (4,600 ft).
