Small, colourful macaw. Pale green body with blue edge of wing, primary coverts and flight feathers. Blue head with small grey bare face patch extending from bill around eye. Medium-sized grey bill. Red uppertail, shading to pale blue at tip. Underside of wings and tail dusky yellow. Primolius couloni occurs in eastern Peru, extreme western Brazil, and north-western Bolivia. In some locations within its range it is considered not uncommon, but in other areas it appears to be scarce, or even absent. It has been recorded throughout the year at some locations, but numbers elsewhere seem to vary seasonally and the species may wander in response to food availability.