The bronze-tailed thornbill (Chalcostigma heteropogon) is a species of hummingbird in the "coquettes", tribe Lesbiini of subfamily Lesbiinae.

Adult females are similar but the gorget is paler green and does not have the pink "beard"; in addition their outer tail feathers have pale tips.

[6] The bronze-tailed thornbill is found from the Tamá Massif of extreme western Venezuela through the Eastern Andes of Colombia as far south as Cundinamarca Department.

It inhabits steep rocky slopes within semi-arid to humid páramo grasslands and also the edges of Polylepis and other stunted woodland.

[6] The bronze-tailed thornbill's breeding season is thought to span from September to January but may extend further at either end.