The Long-winged Antwren is, along with the Gray Antwren (Myrmotherula menetriesii), one of the most widely distributed species in the "gray antwren" group of Myrmotherula, and occurs throughout much of Amazonia. This is a small, short-tailed antwren. The male Long-winged Antwren is primarily light gray, except for the broad black throat patch, and the black wing coverts with white tips. The plumage of the female varies geographically, but is primarily buffy brown, and in some populations closely resembles the female of Gray Antwren. The Long-winged Antwren is a regular member of mixed species flocks in Amazonia; singles, pairs, or family groups forage in association with other insectivorous birds, including Thamnomanes antshrikes and other species of Myrmotherula antwrens, as well as ovenbirds (Furnariidae), woodcreepers (Dendrocolaptidae) and other species. Long-winged Antwrens typically forage in the midstory, below the foraging height of Gray Antwren, but there is overlap in foraging height between these two species. The song of Long-winged Antwren is very different from the song of Gray Antwren, but is similar to the song of the Band-tailed Antwren (Myrmotherula urosticta) of eastern Brazil.