The green-backed firecrown (Sephanoides sephaniodes) is a hummingbird that is found in Argentina and Chile. It can be fairly common in some locations, especially on Robinson Crusoe Island, 350 miles off the Chilean coast. It can be found in the Chilean matorral ecoregion, extending as far south as Tierra del Fuego.
Like its cousin the Juan Fernández firecrown, the green-backed firecrown often hangs from flower petals or leaves with its feet. Their nests are built in high branches or bushes. source