Rufous-rumped Antwren

The rufous-rumped antwren is 10 to 12 cm (3.9 to 4.7 in) long and weighs about 7 to 9.5 g (0.25 to 0.34 oz). It is small, slender, and long-tailed, and somewhat resembles a greenlet or New World warbler. The sexes have different plumage. Adult males of the nominate subspecies E. c. callinota have blackish lores and line through the eye on an otherwise pale gray face. Their crown and nape are black, their upper back olive, their lower back and rump bright rufous or orange brown, and their uppertail coverts olive. Their tail is dusky with olive edges on the feathers. Voice: The rufous-rumped antwren's song is described as "a rapidly uttered, high-pitched tsii-tsii-tsi-tsi-titititititititi that accelerates into a fast chipper or trill" and similarly as "an accelerating, rising series of high, thin notes ending in a falling, chippering trill: tew tew-tew-ti-ti-ti't't't't't't'ti". Its calls include "high tsi and ti notes".