Rufous-bellied Antwren

The rufous-bellied antwren is 8.5 to 9.5 cm (3.3 to 3.7 in) long and weighs 8.5 to 11 g (0.30 to 0.39 oz). It has a very short tail. Adult males are mostly gray. They have a white patch between their scapulars and pale cinnamon spots on their uppertail coverts. Their wings and tail are blackish brown with cinnamon edges on the flight feathers and pale cinnamon tips on the wing coverts and tail feathers. Their throat is pale gray and their lower belly, flanks, and crissum are tawny. Adult females have olive-gray upperparts and a grayish olive breast; they are otherwise like males.

The rufous-bellied antwren is found in from southern Venezuela's Bolívar and Amazonas states east through the Guianas and Brazil north of the Amazon and east of the Negro rivers. It primarily inhabits terra firme evergreen forest. It favors areas with shady undergrowth and much leaf litter, especially near slow-moving streams and somewhat wet spots. In elevation it occurs from sea level to 600 m (2,000 ft).

The rufous-bellied antwren's diet has not been detailed but includes insects and spiders. It mostly forages singly or in pairs, and joins mixed-species feeding flocks while they pass through the antwren's territory. It typically forages from the ground up to within about 1 m (3 ft) above it but will feed as high as 2 m (7 ft). It actively gleans from leaves, stems, and branches by reaching from a perch and making short jumps while hitching up vertical stems and vines. It has been observed following army ant swarms in Brazil, Guyana, and Suriname.