Southern Emerald-Toucanet, a small toucan of the Andes, is the South American counterpart to Northern Emerald-Toucanet (Aulacorhynchus prasinus) of Central America. Like other species of Aulacorhynchus, it is primarily bright green, with a white or blue throat, and rufous undertail coverts and rufous tips to the rectrices. This species is quite variable geographically, containing subspecies. The subspecies differ subtly in size, and more dramatically in the color of the throat (white, pale gray, blue, or black) and the pattern of the bill. The bill is black and yellow in all populations, but the extent of the yellow may cover most of the culmen (most subspecies) or be restricted to the tip of the bill in some populations. Southern Emerald-Toucanet typically forages on fruit and small vertebrates in humid forest, frequently moving together in small flocks. The biology of this species presumably is very similar to that of Northern Emerald-Toucanet, but, in contrast to the Central American species, Southern Emerald-Toucanet is much less well-known.