Small, arboreal bird of tepui highlands. Olive-gray above and yellowish below, with a gray head, pinkish bill, and pale eye. One of the most widespread tepui endemics, it occurs in both tall and stunted forest on tepui slopes and on isolated formations at elevations as low as 500 meters. Forages actively, searching foliage for insects and often joining mixed-species flocks. Usually heard before it is seen. Song is a distinctive two-parted whistle, with varying degrees of inflection, the second note lower-pitched. Also gives harsh scold notes like other vireos. Most similar to Lemon-chested Greenlet but has very different voice and occurs at higher elevations.