A small and rather plain flycatcher of light woodland and scrub. Note especially its round crown (lacking a crest), long eyestripe, and buff wingbars. Ranges east of the Andes from Peru to southeastern Brazil and northern Argentina; may overlap with the very similar Northern Mouse-colored Tyrannulet in central Brazil. These species were split based largely on genetic differences, and field identification in parts of Brazil may be impossible without further study. Typical song is a buzzy trill that first rises and then falls abruptly at the end.