Reiser's Tyrannulet

Reiser's tyrannulet is 11 to 11.5 cm (4.3 to 4.5 in) long and weighs 7 to 8 g (0.25 to 0.28 oz). The sexes have the same plumage. Adults have a bright olive crown, nape, back, and rump with faint grayish tips on the crown feathers. They have yellowish white lores, supercilium, and cheeks and a thin olive line through the eye. Their wings are dusky with pale yellowish edges on the flight feathers and the ends of the coverts; the last show as two bars on the closed wing. Their tail is dusky olive. 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.

Reiser's tyrannulet is found from southern Piauí state in Brazil southwest into east-central Paraguay's Concepción Department. It inhabits subtropical dry deciduous forest and, in the cerrado region, gallery forest .

The diet and foraging behavior of Reiser's tyrannulet have not been studied. It is thought to forage in the canopy and on the edges of the forest.