They have yellowish white lores, supercilium, and cheeks and a thin olive line through the eye.

Their throat and lower face are whitish and their underparts pale yellow with faint olive streaks on the breast and sides.

Their iris is pale brown, their short rounded bill has a blackish maxilla and a black-tipped pinkish to white mandible, and their legs and feet are gray.

[4][5][6] Reiser's tyrannulet is found from southern Piauí state in Brazil southwest into east-central Paraguay's Concepción Department.

The song of Reiser's tyrannulet is a "series of rough, liquid notes moving down the scale, 'briu-briu-briu-briu-briu-briu-briu' ".

"Severe degradation, destruction and fragmentation of cerradão habitat has already taken place and is ongoing...Its conservation status should be carefully re-evaluated, with a view to possible uplisting to Near Threatened.