 The taxonomy of this and related species and genera have been problematic; more information may be
found under "Sun conure#Taxonomy".Based on size, morphology, and plumage, this species is believed to be a close living relative of the extinct Carolina parakeet, possibly the closest, though that has not been confirmed by molecular phylogenetics which found the nanday parakeet to be the Carolina parakeet's closest living relative among the species tested.The plumage of this bird is very close to that of the Carolina's and can be distinguished from the Carolina parakeet by having a yellow neck and shoulders, and a black beak instead of a buff-colored beak as the Carolina parakeet had.