Myrmotherula fluminensis
The Rio de Janeiro Antwren (Myrmotherula fluminensis) is a diminutive and highly range-restricted passerine belonging to the antbird family Thamnophilidae, measuring approximately 9-10 cm in length and weighing around 7-8 grams. Males are characterized by their overall gray plumage, a prominent black throat and upper breast patch often subtly streaked with white, and two distinct white wing-bars; their underparts are a paler gray. Females exhibit striking sexual dimorphism, sporting a rufous-...
This species inhabits the understory of humid lowland Atlantic Forest, specifically favoring dense bamboo thickets, vine tangles, and secondary growth at elevations typically below 200 meters.
Primarily insectivorous, feeding on small arthropods such as insects and spiders, which it gleans from foliage and bark.
The Rio de Janeiro Antwren is a diurnal and rather secretive bird, spending most of its time foraging within dense understory vegetation. It employs a gleaning foraging strategy, meticulously picking small insects and spiders from foliage, branches, and bark, often performing quick sallies or sho...
The Rio de Janeiro Antwren is an extreme endemic, restricted entirely to a tiny, highly fragmented range within the state of Rio de Janeiro, Brazil. Its distribution is confined to the humid lowlands of the Paraíba do Sul River basin, generally at elevations below 200 meters. Key known localities...
Critically Endangered
- The Rio de Janeiro Antwren was only formally described as a distinct species in 1988, making it a relatively recent ornithological discovery. - It was initially considered a subspecies of the Salvadori's Antwren (*Myrmotherula minor*) for many years before being elevated to full species status....