The Scaly-breasted Hummingbird, also known as the Scaly-breasted Sabrewing, is a member of the "emeralds" tribe Trochilini within the hummingbird family. This species, Phaeochroa cuvierii, exhibits a bronzy green plumage with a distinctive grayish buff belly. The underparts are adorned with buffy edges on the feathers, creating a scaly appearance. The tail is primarily bronzy with white tips on the outer feathers.
Adults measure between 11.5 to 13 cm in length and weigh approximately 8 to 10 grams. Both sexes share similar plumage, though females possess a longer bill. The bill is mostly black with a pink base on the mandible, except for the subspecies P. c. roberti, which has an entirely black bill.
This hummingbird favors semi-open to open landscapes, including dry forests, forest edges and clearings, mangroves, secondary forests, scrublands, and gardens. It avoids the interiors of dense forests and is typically found from the understory to the mid-strata, and occasionally in the canopy at forest edges.
The Scaly-breasted Hummingbird is found across a range of countries, including Belize, Colombia, Costa Rica, Guatemala, Honduras, Mexico, Nicaragua, and Panama. It is generally a lowland species but can be found at elevations up to 1,200 meters in Costa Rica.
Primarily sedentary, this hummingbird may make local movements to exploit flowering events. It is known for aggressively defending flower patches and asserting dominance over smaller hummingbird species.
The song of the Scaly-breasted Hummingbird is a loud, variable warble consisting of chips, sharp squeaks, and short trills. It also produces a high-pitched descending trill during chases and other calls such as a short burry 'trrk', a wet 'tlek', and a more emphatic 'chick'.
Breeding typically occurs during the rainy season, with males displaying at leks to attract females. The female builds a cup-shaped nest adorned with moss and lichen, placed on a horizontal branch. Incubation of the two eggs lasts 17 to 19 days, with fledging occurring 22 to 29 days post-hatch.
The diet consists of nectar from various flowering trees, shrubs, and bromeliads, which it consumes by both hovering and perching. In addition to nectar, it also feeds on arthropods through hawking and gleaning from vegetation.
The IUCN has classified the Scaly-breasted Hummingbird as Least Concern. It boasts a large range and a stable population estimated at over 50,000 mature individuals. The species is considered uncommon to locally common and is present in several protected areas.