Glittering-throated Emerald

The glittering-throated emerald is 8 to 12 cm (3.1 to 4.7 in) long and weighs 3.5 to 6.2 g (0.12 to 0.22 oz). Both sexes have a straight bill with a blackish maxilla and a pinkish mandible with a dark tip; its length varies among the subspecies. Adult males of the nominate subspecies C. f. fimbriata have golden- to bronze-green upperparts and a dark bronze-green to blackish bronze tail. Their throat and most of their breast are glittering golden-green. The center of their lower breast and their belly are white and their undertail coverts white with brownish centers. Adult females are similar to the male with the addition of white bars near the end of their throat feathers and greenish-gray tips on their outermost tail feathers. Juveniles resemble the adult female but with a more grayish-brown breast. Subspecies C. f. elegantissima has coppery to purplish uppertail coverts. C. f. apicalis and C. f. fluviatilis have significantly longer bills than the nominate. C. f. fluviatilis also has a turquoise to bluish sheen on its throat, a characteristic shared with C. f. laeta. Subspecies C. f. nigricauda and C. f. tephrocephala have completely white undertail coverts and greenish-black to bluish black tails. C. f. tephrocephala is slightly heavier than the nominate and also significantly larger in all dimensions.

The subspecies of glittering-throated emerald are found thus:

C. f. elegantissima, northern and western Venezuela and adjoining extreme northeastern Colombia C. f. fimbriata, from the Orinoco Basin of northeastern Venezuela through the Guianas and in northern Brazil north of the Amazon C. f. apicalis, Colombia east of the Andes C. f. fluviatilis, southeastern Colombia and eastern Ecuador C. f. laeta, northeastern Peru's departments of Amazonas, Loreto, San Martín, and Ucayali and possibly western Brazil C. f. nigricauda, eastern Bolivia and central and eastern Brazil south of the Amazon C. f. tephrocephala, coastal southeastern Brazil from Espírito Santo south to Rio Grande do Sul The glittering-throated emerald inhabits a wide variety of semi-open to open landscapes, shunning the interior of dense forest. It is found in less dense dry and humid forest, gallery forest, secondary forest, open woodland, savanna, scrublands, caatinga, plantations, and gardens. C. f. tephrocephala is also found in mangroves.

The glittering-throated emerald forages for nectar at a very large variety of flowering herbs, bushes, vines, and trees. Many species of at least 10 families are known sources. It forages by trap-lining, visiting a circuit of flowers, and seldom feeds higher than the lower strata of trees. In addition to nectar it feeds on small insects.