Family Tyrant-flycatchers (Tyrannidae)

Near Threatened

Chico's Tyrannulet (Zimmerius chicomendesi)


French: Tyranneau de Mendes German: Grünkleintyrann Spanish: Mosquerito de Chico Mendes

Zimmerius chicomendesi

Whitney et al.

, 2013,

municipality of Humaitá on the BR-230 (“Transamazônica”) highway (07°47’22” S, 62°23’32” W), at about 70 m elevation, Amazonas, Brazil


Newly described species#R, in plumage identical to its closest relative Z. villarejoi but differing in its rather smaller size (effect size for male wing −2.43, although sample size small; 2); call clearly with lower minimum frequency (ns[2]); and song (based on published evidence#R) at least 1 kHz lower in minimum frequency (3), with frequency range much larger (2). Described as interfluvial campina specialist#R, but this appears to apply also to Z. villarejoi. Acceptance of species status here depends on fortification of evidence concerning morphometric differences, and on chance to assess loudsong evidence when recordings available. Monotypic.


C Amazonian Brazil (R Madeira to R Aripuanã and R Madeirinha, in SE Amazonas; possibly also in adjacent NE Rondônia and NW Mato Grosso).

Descriptive notes

10 cm; 5·5 g (one male). Typical Zimmerius tyrannulet, with uniform olive-green upperparts from head to uppertail-coverts, becoming paler green over face, throat,... read more


Four types of vocalizations known—song, common call, call series and a snarl (the latter probably... read more


Strictly confined to lowland campina woodland and scrub on level ground, with sandy and... read more

Food and feeding

Diet appears to be heavily based on fruits of the mistletoe Oryctanthus alveolatus (Loranthaceae), which plant is also important... read more


Nothing known, with no evidence of breeding in either Aug or Dec based on observations and collected specimens.


Presumably sedentary.

Status and conservation

Not globally threatened. Currently considered Near Threatened. Difficult to find unless voice is known and was previously overlooked, even by observers with substantial... read more

Recommended citation

del Hoyo, J., Collar, N. & Kirwan, G.M. (2019). Chico's Tyrannulet (Zimmerius chicomendesi). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from on 12 December 2019).