About Chionomesa lactea (R.Lesson, 1832)
The sapphire-spangled emerald (Chionomesa lactea) measures 8 to 11 cm (3.1 to 4.3 in) long and weighs 3.6 to 5 g (0.13 to 0.18 oz). For all subspecies, both sexes share the same bill characteristics: it is a medium-length straight bill, with a blackish upper mandible (maxilla) and a pinkish to horn-colored lower mandible (mandible) that has a darkish to blackish tip. Males of the nominate subspecies C. l. lactea have golden- to bronze-green upperparts, with bronze-green coloring on the crown, neck, and flanks. Their throat and upper breast are glittering violet-blue, the center of their lower breast is white, their belly is grayish, and their undertail coverts are whitish with brown streaks. The central tail feathers have shining green or bronzy green bases that darken toward the tip, and the outer tail feathers are bluish black. Adult females are similar overall to nominate males, but they have a grayish throat with glittering turquoise spots, and their outermost tail feathers have grayish tips. Juveniles resemble adult females, but have much more gray coloring on their underparts. Males of subspecies C. l. zimmeri have a smaller glittering violet-blue patch than the nominate subspecies, and this patch does not extend from the throat onto the breast. Females of C. l. zimmeri have a whiter throat and belly than the nominate. Males of C. l. bartletti have a brighter green crown than the nominate, a grayish fringe on their throat feathers, a greenish center to the belly, a grayish lower belly, and much more brown on the undertail coverts. Females of C. l. bartletti resemble the subspecies' males but are duller; their throat and breast have white and gray flecks, and their belly is whiter than that of the nominate subspecies. The three subspecies of sapphire-spangled emerald occupy distinct, separate ranges. C. l. zimmeri is the northernmost subspecies, and is found only in Bolívar state, southeastern Venezuela. The nominate C. l. lactea occurs in eastern Brazil, ranging from Bahia south through Minas Gerais, Rio de Janeiro, and São Paulo into Paraná. It has also been recorded as a vagrant in northern Argentina. C. l. bartletti is found in eastern and southeastern Peru, northern Bolivia, and adjacent western Brazil. There is at least one undocumented record from extreme eastern Ecuador, and the SACC classifies the species as hypothetical there. As a species, the sapphire-spangled emerald generally inhabits semi-open landscapes, including rainforest edges, gallery forest, secondary forest, river edges, and clearings. It mostly occurs at elevations below 1,000 m (3,300 ft), but in Venezuela it occupies a narrow elevational range between 1,100 to 1,400 m (3,600 to 4,600 ft). In addition to the semi-open landscapes the species favors generally, the nominate C. l. lactea is also found in open cerrado, campos rupestres, parks, and gardens. Most of this subspecies' range is near sea level, but it has been recorded locally at elevations as high as about 1,300 m (4,300 ft).
