The white-chested emerald (Chrysuronia brevirostris) is a hummingbird in the "emeralds", tribe Trochilini of subfamily Trochilinae. It is found in Brazil, the Guianas, Trinidad, and Venezuela.
Taxonomy and systematics
The white-chested emerald's taxonomic history is complex. The species was previously known in succession as Amazilia chionopectus, Agyrtria brevirostris, and Amazilia brevirostris. A molecular phylogenetic study published in 2014 found that Amazilia was polyphyletic. In the revised classification to create monophyletic genera, the white-chested emerald was moved by most taxonomic systems to Chrysuronia. However, BirdLife International's Handbook of the Birds of the World retains it in Amazilia.
Subspecies C. b. chionopectus is significantly larger than the other two subspecies but has the same plumage as the nominate. C. b. orienticola is similar to the nominate but has darker, more bronze colored, upperparts and flanks.