Rio de Janeiro Antwren Myrmotherula fluminensis

Enigmatic and controversial species known only from a single male specimen taken in 1982 in lowland rainforest in the state of Rio de Janeiro in southeastern Brazil. It has not been seen with any certainty since then. Small and short-tailed. Male is gray with a black bib and white wingbars. Similar to White-flanked Antwren, but lacks pale sides; also similar to Salvadori’s Antwren, but has a larger black bib. Female plumage is unknown. Some ornithologists have suggested that this species could be a hybrid or an aberrant individual of White-flanked Antwren.