Rufous-margined Antwren

Overview

The rufous-margined antwren (Herpsilochmus rufimarginatus) is an insectivorous bird belonging to the family Thamnophilidae. It is currently classified as a monotypic species within the 'typical antbirds' subfamily.

Identification

• Length of 10 to 12.5 cm with a black crown, wide whitish supercilium, and black eye-stripe in males, while females display rufous foreheads and rufous-brown crowns.
• Upperparts are primarily olive-gray with scattered black patches, featuring bright cinnamon-rufous edges on the flight feathers and white tips on the wing coverts.
• Throat and underparts are light yellow with an olive tinge on the sides, and the tail is dark gray with white tips.
• Song consists of three to four slow-paced notes rising in frequency, followed by a series of fast notes that decelerate; pairs often sing in duet.

Habitat

Found in a disjunct range across parts of Brazil, Paraguay, and northeastern Argentina, primarily inhabiting the interior of humid evergreen Atlantic Forest and less often its edges.

• It also occupies restinga woodlands on white-sand soils and typically ranges in elevation from sea level to approximately 1,100 m.
• The species favours dense vine tangles within the forest mid-storey to subcanopy layers.

Diet

Diet consists mainly of insects and spiders, though the bird also feeds on Rapanea mistletoe berries.

• It forages actively and methodically, gleaning prey from leaves, stems, and vines by reaching or lunging from a perch, occasionally making short sallies to the underside of leaves.
• It does not follow army ant swarms.

Did you know?

The taxonomy of this species is unsettled, with different authorities having historically treated it as part of the rufous-winged antwren before splitting it into the monotypic rufous-margined antwren or designating it as the southern rufous-winged antwren.