The rufous-margined antwren (Herpsilochmus rufimarginatus) is an insectivorous bird in subfamily Thamnophilinae of family Thamnophilidae, the "typical antbirds."

[1] The rufous-margined antwren was described by the Dutch zoologist Coenraad Jacob Temminck in 1822 and given the binomial name Myiothera rufimarginata.

[11] This article follows the majority treatment of a monotypic rufous-margined antwren in which "scapularis" is included but not as a subspecies.

Their upperparts are mostly olive-gray with scattered black patches, yellow uppertail coverts, and white tips on their outer scapulars.

Their wing coverts are black with white tips; their flight feathers are olive-brown tinged dark gray with bright cinnamon-rufous edges.

A small population is found north of the Rio São Francisco in Brazil's Pernambuco state.

It primarily inhabits the interior of humid evergreen Atlantic Forest, less often its edges, and locally in restinga woodlands on white-sand soils.

It forages actively and methodically, and usually captures prey by gleaning from leaves, stems, and vines by reaching and sometimes lunging from a perch.

Its most common call is a "melodious whistled note tew" that may be repeated up to five times in a burst or irregularly over a longer period.

[12] The IUCN follows HBW taxonomy and so its assessement of H. rufimarginatus as the "southern rufous-winged antwren" does not include "scapularis".