Male - Head: matt black with large white cheek patches. - Upperparts: green-olive with a blue-grey wing. - Underparts: yellow with a broad, continuous black stripe running from throat to vent. - Tail: blue-grey with white outer feathers.
Female The female resembles the male but has a narrower, sometimes broken breast stripe — the most reliable criterion for sexing. The yellow of the underparts is a little paler, and the green of the back slightly duller.
Juvenile Juveniles have yellower cheeks (not white) and duller colours. The breast stripe is fainter. They change into adult plumage during the autumn moult.