The rufous-capped thornbill (Chalcostigma ruficeps) is a species of hummingbird in the "coquettes", tribe Lesbiini of subfamily Lesbiinae.

[7] The rufous-capped thornbill is found on the east slope of the Andes from southeastern Ecuador's Zamora-Chinchipe Province through Peru into Bolivia as far as Cochabamba Department.

[7] The rufous-capped thornbill feeds on nectar from a variety of flowers, mostly in the family Melastomataceae.

It sometimes "robs" nectar by piercing the base of a flower or by feeding at holes made by Diglossa flowerpiercers.

[7] The rufous-capped thornbill's breeding season spans from December to March in Bolivia and perhaps July to October in Peru.

The rufous-capped thornbill's vocalizations are not well known, but do include "a short dry double rattle 'trr-trr'" and "a rising/falling twitter 't-tr-tr-tsee-tseee-tititrrr'.