32 cm.. length between 173 and 334 g. of weight.
The Blue-backed Parrot (Tanygnathus sumatranus) has the head and the the mantle a light yellowish green (slightly more yellowish mantle). The low back, buttocks and uppertail-coverts strongly impregnated with light blue.
Wings Green darker that the the mantle, with fine verde-amarillentos margins to coverts; primary coverts Blue sharp; bend of wing turquoise blue color marked; primaries Foreign and blackish green in vane inner.
Wing feathers greenish yellow; underside of flight feather, blackish. The underparts yellowish-green illuminated.
Upper, the tail green, marked in yellow on the vane inmates of the lateral feathers; Under, the tail varies from the color yellow to the Brown dark.
Bill red; irises yellow; legs grey.
It presents sexual dimorphism. The female has the bill yellowish or whitish grey; less greenish-yellow in the the mantle and less blue in the under wing-coverts.
Male young acquires the bill Red after ten to twelve months.
- Sound of the Blue-backed Parrot.