The three species are respectively found in eastern Australia, Papua, the Moluccas and other Indonesian islands.

Predominantly of red and green plumage, the long-tailed parrots are related to the genera Aprosmictus and Polytelis.

Red plumage covers the lower abdomen, and the pale-green wing band is small or absent.

Classified in the subfamily Psittacinae within the true parrot family, the genus Alisterus was described by Australian amateur ornithologist Gregory Mathews in 1911.

The king parrots appear to be most closely related to the genera Aprosmictus and the long-tailed parrots of the genus Polytelis, united by similarities in food begging and contact calls by chicks, and by more recent molecular analysis in 2005.