The western rosella, or moyadong, is a species of parrot endemic to southwestern Australia. The head and underparts are bright red, and the back is mottled black; a yellow patch at the cheek distinguishes it from others of the genus Platycercus. Adults of the species exhibit sexual dimorphism with the females duller overall; juveniles lack the striking colours of mature birds and the characteristic patterning is not as easily distinguished. Their communication call is a softly delivered pink-pink sound, and much of their behaviour is comparatively unobtrusive. Their habitat is in eucalypt forests and woodlands, where they often remain unobserved until they appear to feed on seeds at nearby cleared areas.

Rosellas are in a genus that consists of six species and nineteen subspecies. These colourful parrots from Australia are in the genus Platycercus. Platycercus means "broad-tailed" or "flat-tailed", reflecting a feature common to the rosellas and other members of the broad-tailed parrot tribe. Their diet is mainly seeds and fruit.