Generally rare (but locally fairly common in a few spots) hummingbird of humid forests just below treeline on the eastern slope of the Andes from NW Argentina to La Paz, Bolivia. Often feeds near treefalls and roadcuts, especially on bellflowers (Lobelioideae). Seemingly more common in southern half of range. Male’s white leg puffs and blue crown are distinctive. Female’s orange underparts combined with metallic blue undertail coverts also unique.