About Chionomesa fimbriata (J.F.Gmelin, 1788)
The glittering-throated emerald (Chionomesa fimbriata) measures 8 to 12 cm (3.1 to 4.7 in) in length and weighs 3.5 to 6.2 g (0.12 to 0.22 oz). Both sexes have a straight bill: the maxilla is blackish, the mandible is pinkish with a dark tip, and bill length varies between subspecies. For the nominate subspecies C. f. fimbriata, adult males have golden to bronze-green upperparts and a dark bronze-green to blackish bronze tail. Their throat and most of the breast are glittering golden-green, while the center of the lower breast and belly are white, and the undertail coverts are white with brownish centers. Adult females are similar to males, but have additional white bars near the tip of their throat feathers and greenish-gray tips on their outermost tail feathers. Juveniles look similar to adult females, but have a more grayish-brown breast. Several subspecies have distinct traits: C. f. elegantissima has coppery to purplish uppertail coverts. C. f. apicalis and C. f. fluviatilis have significantly longer bills than the nominate subspecies. C. f. fluviatilis has a turquoise to bluish throat sheen, a trait it shares with C. f. laeta. C. f. nigricauda and C. f. tephrocephala have fully white undertail coverts and greenish-black to bluish black tails. C. f. tephrocephala is slightly heavier than the nominate subspecies, and is significantly larger in all measurements. The subspecies of glittering-throated emerald are distributed as follows: C. f. elegantissima occurs in northern and western Venezuela, and the adjacent extreme northeastern Colombia. C. f. fimbriata ranges from the Orinoco Basin of northeastern Venezuela through the Guianas, and in northern Brazil north of the Amazon. C. f. apicalis is found in Colombia east of the Andes. C. f. fluviatilis occurs in southeastern Colombia and eastern Ecuador. C. f. laeta is found in the Amazonas, Loreto, San Martín, and Ucayali departments of northeastern Peru, and possibly in western Brazil. C. f. nigricauda occurs in eastern Bolivia, and central and eastern Brazil south of the Amazon. C. f. tephrocephala is found in coastal southeastern Brazil, from Espírito Santo south to Rio Grande do Sul. The glittering-throated emerald lives in a wide variety of semi-open to open landscapes, and avoids the interior of dense forest. It can be found in less dense dry and humid forest, gallery forest, secondary forest, open woodland, savanna, scrublands, caatinga, plantations, and gardens. The subspecies C. f. tephrocephala is also found in mangroves.
