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Guianan Tyrannulet Zimmerius acer

  • © Anselmo d'Affonseca

A recent split from the widespread Slender-footed Tyrannulet (Zimmerius gracilipes), the Guianan Tyrannulet occupies the northeast portion of the wider species’ Amazonian range, being almost exclusively found north of the Amazon and east of the Rio Negro, across northern Brazil and the Guianas. There is also an isolated population, traditionally ascribed to the same taxon when it was regarded as a subspecies of the Slender-footed Tyrannulet, in extreme northeast Brazil, and this potentially anomalous situation requires additional research. This ‘new’ species is generally very similar in plumage to its western and southern counterpart, being principally olive-green, with narrow yellowish fringes to the wing feathers, but no wing bars, a slightly grayer cast to the head, a grizzled face, and pale yellowish underparts. It is generally found in humid lowland forest and tall second growth.

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© Curtis Marantz

  • Year-round
  • Migration
  • Breeding
  • Non-Breeding

Recommended Citation

Guianan Tyrannulet (Zimmerius acer), In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. retrieved from Neotropical Birds Online: