The Guianan Tyrannulet is a small bird of humid lowland forest, foraging high in the canopy north of the Amazon. Its reported range includes eastern Venezuela, the Guianas and northern Brazil. A population south of the river may represent a different, undescribed species.
About 10.5 cm long, it has olive-brown upperparts, yellow-edged wing feathers, a yellow underside and a pale yellow throat.
It searches for insects and small fruit high in the canopy of humid lowland forest.
An extinction-risk assessment has not been added yet.