The Nanday Conure (Nandayus nenday) occurs in central-southern South America (southeastern Bolivia and southwestern Brazil through central Paraguay to northern Argentina), where it is generally found in open country, sometimes walking on the ground; feral populations occur elsewhere (e.g., Buenos Aires, California, and Florida). Nanday Conures often associate with Monk Parakeets (Myiopsitta monachus) in mixed flocks and are usually quite tame and approachable. They are generally common and locally abundant.
Nanday Conures inhabit open lowlands up to around 800 m, including moister parts of the eastern chaco, pantanal, and cattle rangelands with palms. They are gregarious, with groups of up to a dozen birds when breeding and several hundred gathered when roosting. They are often seen drinking at waterholes. They nest in cavities in trees or large fenceposts, producing a clutch of 4 eggs.
According to a mtDNA-based phylogenetic analysis of the genus Aratinga by Ribas and Miyaki (2004), the Nanday Conure forms a monophyletic group with the Sun Conure (A. solstitialis), Jenday Conure (A. jandaya), and Golden-capped Conure (A. auricapilla).
(Collar 1997 and references therein; Juniper and Parr 1998 and references therein)