The Blue-chinned Sapphire, Chlorostilbon notatus, is a hummingbird that breeds from Colombia south and east to the Guianas, Trinidad, Peru, and Brazil. There have been occasional records from Tobago. For Brazil, the species' range is along the main Amazon River Basin, as well as the coastal Atlantic Ocean, both in the northeast, as well as far south on the southeast coastal strip, (an entire coastal strip, north-east-south of about 3000 km). It is often placed in the monotypic genus Chlorestes instead of Chlorostilbon.

It is a bird of forests and sometimes cultivated areas with large trees. The female lays her eggs in a deep cup nest, made of lichen and other fine plant material and placed on a horizontal tree branch. Incubation is 16 days with a further 18-19 days to fledging.

The Blue-chinned Sapphire is 8.9 cm long and weighs 3.8 g. The bill is fairly straight, with the upper mandible black and the lower reddish. The male has mainly green plumage, darker above, with white thighs, a forked metallic blue tail and blue upper throat. The female differs from the male in that she has green-spotted white underparts.

Blue-chinned Sapphires feed on insects and nectar, mainly in trees but sometimes on vines or smaller plants like Heliconia. The song is a high metallic ssooo-ssooo-ssooo.