The Red-shouldered macaw, at 30 cm (12 in) long and 165 gm (5.8 oz) in weight, is the smallest of all the macaws. Like all macaws, it has a long narrow tail and a large head.
It has bright green feathers on the body, with dark or slate blue feathers on the head just above the beak. The wings and tail have feathers that are bright green above and olive-green below.
The leading edges of the wings, especially on the underside, are red. (These red feathers appear at puberty.) Their eyes are orange, and the skin around the eyes is white without feathers, just as in the larger macaws. This bare patch of facial skin is smaller in proportion to the head than the one seen in most larger macaws. (Wikipedia)