Large, stout wren-babbler. Highly dependent on pristine lowland forests; populations now declining and increasingly fragmented across Borneo as that habitat is rapidly deforested. Shy, foraging quietly under dense cover and amongst fallen trunks, usually in pairs or small groups. Best detected by song, a simple but beautiful two-note series of mournful, clear whistles: “doooo-deeee.” If seen well, note whitish face, white-and-black-streaked underparts, brown back, and pot-bellied appearance.