Alisterus

Description

Medium-sized parrots, 35–43 cm (14–17 in) in length with long, broad tails. They have relatively small beaks for their size. The beaks of the adults are two colours, blackish and orange-reddish, except for the subspecies of the Moluccan king parrot, Alisterus amboinensis buruensis, which has a grey-black beak, and female of the Australian species, Alisterus scapularis, which has a grey beak.

Sexual dimorphism

The Papuan king parrot and the Australian king parrot show sexual dimorphism in their plumage and beak colouration, which contrast to the Moluccan king parrot, where the male and female have an identical external appearance.

The two subspecies of the Australian king parrot are similar except in size. The male has a red head and neck, red lower parts, blue back and rump, and green wings, each with a pale-green band (resembling a shoulder stripe). In the female, the head is green, the green being continuous over the neck, chest, and back. Red plumage covers the lower abdomen, and the pale-green wing band is small or absent. Juvenile males also have a green neck and head.

The three subspecies of the Papuan king parrot all show sexual dimorphism and in all three subspecies, the males can be identified by prominent broad pale-green bands on each wing. The differences in the females between subspecies are more marked than the differences in the males. The female of subspecies A. chloropterus moszkowskii has green wings, and a red head, neck, chest, and abdomen resembling the male, and differs from the male with its much smaller pale-green wing band. The females of A. chloropterus chloropterus and A. chloropterus calloterus differ from the males with broadly similar sexual dimorphism to the Australian king parrot with extended green plumage, except the chests of the females of these two Papuan king parrot subspecies have vague transverse green and red striations.