Both adults in general green, lower underparts being paler; white forehead and forecrown, the feathers grey just before the tips and orange/red tipped on forehead; dark grey ear coverts marked with pink; white cheeks and lores, dark grey edging on the feathers; feathers on forecheeks sometimes edged with orange/red; throat has pink band, turning to red/purple on chest and further blending with brown on abdomen; red undertail coverts; green tail with red at base. Bill pale olive/yellow. Eye ring bare and pale grey. Eye brown.
Feathers on head green with white bases showing; feathers on crown edged with dull red; white sides of head, with margined green feathers; green throat and breast, the feathers with dull red/mauve in centre.
Calls are described as distinctive; in flight a smooth series of notes with a laughing tone, also harsher notes. While perched calls take on a nasal tone.
Content Sources:
Article "The Genus Pionus," by C.T.E. Partridge http://www.upatsix.com/faq/pionus.htm
Animal World http://animal-world.com/encyclo/birds/pionus/PionusProfile.htm
Parrots: A Guide to Parrots of the World, Juniper and Parr, 1998.
Parrots of the World, Forshaw and Cooper, 1977.
Parrots of the World, Forshaw, 2006.
Parrots in Aviculture, Low, 1992.
Parrots: Their Care and Breeding, Low, 1986.