Russet-bellied Spinetail

The russet-bellied spinetail is 16.5 to 17 cm (6.5 to 6.7 in) long and weighs 12 to 14 g (0.42 to 0.49 oz). The sexes have the same plumage. Adults have a faint gray-white supercilium, a distinct but broken white eyering, and blackish lores on an otherwise gray face. Their crown is gray, their back and rump olivaceous gray, and their uppertail coverts bright rufous. Their wing coverts are almost chestnut and the flight feathers brownish. Their tail's central pair of feathers are dark fuscous; the feathers become progressively more rufous to the outermost. Voice: The russet-bellied spinetail's song is "a mewing or nasal-like prr'kuit kuit", typically sung from deep in vegetation. Its calls include "a nasal tu-vit" and "a squeakier djewit".