Negritos are distinctive short-tailed tyrant flycatchers (Tyrannidae). They are among the least vocal of any "songbird" in that they have no song at all and only short alarm and contact notes. This is the Austral Negrito which is common in open country in southern South America. It is similar to the larger, paler winged Andean Negrito (Lessonia oreas) which replaces it further north. The two were formerly considered to be the same species under the name Rufous-backed Negrito.
Female types such as the top bird seemed to outnumber males by a good margin. Could some of these birds be young males? The literature indicates the female like juvenal plumage is replaced by an "immature" plumage lasting about six months. However, none of my references describe this "immature" (formative?) plumage other than Ridgley & Tudor who make passing mention of males in a patchy immature plumage. If anybody can provide a better reference to the immature plumages of this species, I would be most grateful.
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