The Rio de Janeiro antwren is a bird in subfamily Thamnophilinae of family Thamnophilidae, the "typical antbirds". It is endemic to Brazil.
Region
Atlantic Forest, southeastern Brazil
Typical Environment
Confined to remnants of lowland and foothill Atlantic Forest in the state of Rio de Janeiro. It favors dense, humid understory in evergreen forest, thickets, vine tangles, and secondary growth along forest edges. The species is closely tied to structurally complex leaf-litter and shrub layers where it can glean small arthropods. Extensive urbanization and coastal development have fragmented and reduced its habitat dramatically.
Altitude Range
Sea level to 200 m
Climate Zone
Subtropical
Ease of Keeping
Beginner friendly: 1/5
The Rio de Janeiro antwren is a small, elusive antbird of Brazil’s Atlantic Forest understory, historically known from the state of Rio de Janeiro. It forages in pairs or small family groups, often joining mixed-species flocks. Its plain, subtle plumage makes it easily overlooked, and habitat loss has severely impacted its range. It is considered on the brink of extinction, with few if any recent confirmed records.
Temperament
skulking and wary
Flight Pattern
short rapid wingbeats through understory
Social Behavior
Usually found in pairs or small family groups, keeping close contact while moving through dense cover. Often accompanies mixed-species flocks in the understory. Nests are small, cup-shaped structures placed low in shrubs or vine tangles, with both parents attending the young.
Migratory Pattern
Resident
Song Description
Song is a thin, high-pitched series of quick notes or a short, accelerating trill that can be easily masked by forest background noise. Calls include soft chips and seet-like notes used to maintain contact in dense vegetation.
Plumage
Plain, fine-textured plumage with minimal patterning; male typically uniform gray, female warmer brown with buffy tones below. Wings lack strong bars and the overall appearance is subdued. Feathers lie close to the body, giving a sleek, compact look.
Diet
Primarily small arthropods, including ants, beetles, spiders, and caterpillars. It gleans prey from leaves, twigs, and vine tangles, and occasionally sallies short distances to snatch insects. Foraging is methodical and close to cover, with frequent pauses to scan and listen.
Preferred Environment
Feeds in the shaded understory and lower midstory of humid forest, especially in dense secondary growth and along edges with abundant vine tangles. Often works through bamboo patches and tangled shrubs where prey is concentrated.
