A tiny, stubby, plump dark songbird with a bold red throat in males. Female is nondescript, all gray with a clean white throat. Juveniles resemble female but have a pale-based bill and a green-washed breast. Singles and pairs can be found in lowlands and foothills in a variety of habitats, including forest, forest edge, scrub, and gardens. Male can be separated from male Crimson-crowned Flowerpecker by red throat and lack of red crown. Female Gray-sided differs from female Crimson-crowned in absence of red rump. Song is a thin, high-pitched “see-se-sooo.” Also gives a buzzy “tzjit” note.