Parrots, also known as psittacines (/ˈsɪtəsaɪnz/), are birds of the roughly 398 species[3] in 92 genera comprising the order Psittaciformes (/ˈsɪtəsɪfɔːrmiːz/), found mostly in tropical and subtropical regions. The order is subdivided into three superfamilies: the Psittacoidea ("true" parrots), the Cacatuoidea (cockatoos), and the Strigopoidea (New Zealand parrots). One-third of all parrot species are threatened by extinction, with higher aggregate extinction risk (IUCN Red List Index) than any other comparable bird group. Parrots have a generally pantropical distribution with several species inhabiting temperate regions in the Southern Hemisphere, as well. The greatest diversity of parrots is in South America and Australasia.