Description wikipedia

The rufous-crowned greenlet (Hylophilus poicilotis) is a species of bird in the family Vireonidae, the vireos, greenlets, and shrike-babblers. It is found in Argentina, Brazil, Paraguay, and possibly Bolivia. The rufous-crowned greenlet is about 12.5 cm (4.9 in) long and weighs 9 to 12 g (0.32 to 0.42 oz). The sexes have the same plumage. Adults have a bright chestnut-brown forehead and crown and mottled grayish black ear coverts. Their nape, upper back, and shoulders are olive-green and their lower back and rump are a brighter green. Their wings are dull grayish black with thin greenish edges on the outer webs of the primaries and secondaries and yellow-green edges on the inner webs of the tertials. Their tail is grayish green with brighter greenish edges on the feathers' outer webs. Their throat is dull pale gray, their upper breast yellowish gray, their lower breast dull yellow, their flanks and belly a brighter yellow, and their vent dull yellowish. They have a dark reddish brown iris, a dull blackish maxilla, a gray to dusky pink mandible, and grayish legs and feet. Immatures are similar to adults but with a more olivaceous back and brighter underparts.