Systematics
No consensus existed regarding the taxonomy of Psittaciformes until recently. Consequently, the placement of the Strigopoidea species has been variable in the past. This superfamily is one of three superfamilies in the order Psittaciformes; the other two families are Cacatuoidea (Cockatoos) and Psittacoidea (true parrots). The family is subdivided in two families, Nestoridae with two genera (Nestor and Nelepsittacus) and Strigopidae with a single genus, (Strigops). Traditionally, the species of the superfamily Strigopoidea were placed in the superfamily Psittacoidea, but several studies confirmed the unique placement of this group at the base of the parrot tree. Most authors now recognize this group as its own taxon. with two separate families: Nestoridae and Strigopidae.
Read more about this topic: New Zealand Parrot