It is found in Bolivia, Brazil, Colombia, Ecuador, the Guianas, Peru, Trinidad and Venezuela.

[4][5] The glittering-throated emerald was formally described in 1788 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae.

[6] Gmelin based his description on "L'Oiseau-mouche à gorge tachetée de Cayenne" that had been described and illustrated by the French ornithologist Mathurin Jacques Brisson in 1760, and by the French naturalist Georges-Louis Leclerc, Comte de Buffon in 1779.

In the revised classification to create monophyletic genera, the glittering-throated emerald and the sapphire-spangled emerald (Chionomesa lactea) were moved by most taxonomic systems to the resurrected genus Chionomesa that had been introduced in 1921 by the French naturalist Eugène Simon.

Both sexes have a straight bill with a blackish maxilla and a pinkish mandible with a dark tip; its length varies among the subspecies.

Subspecies C. f. nigricauda and C. f. tephrocephala have completely white undertail coverts and greenish-black to bluish black tails.

[15] Subspecies C. f. tephrocephala of the glittering-throated emerald is known to migrate north and south along the coast.

[15] The glittering-throated emerald forages for nectar at a very large variety of flowering herbs, bushes, vines, and trees.

It forages by trap-lining, visiting a circuit of flowers, and seldom feeds higher than the lower strata of trees.