The sapphire-vented puffleg (Eriocnemis luciani) is a species of hummingbird in the "brilliants", tribe Heliantheini in subfamily Lesbiinae.

[4][6] BirdLife International's Handbook of the Birds of the World accepts several 21st century studies and treats the last two as members a separate species, the coppery-naped puffleg (E.

The nominate subspecies' male has metallic grass green upperparts with a shining dark blue forecrown.

[8] Subspecies E. l. meridae is a more bronzy green than the nominate, its chin emerald to golden, and much of its head feathering has iridescent copper fringes.

[8] The subspecies of sapphire-vented puffleg are found thus (but see the text below):[4][8] Because E. l. meridae is known only from a single 19th century specimen and might be extinct, the SACC does not include Venezuela in the species' range.

[8] The sapphire-vented puffleg forages for nectar at low levels, where it clings to the flowers of shrubs and understory plants.

The one described nest was made of moss, lichen, fern leaves, and spiderweb and was hung from a thin twig in dense grass.