She was daughter of Infanta of Portugal/Archduchess of Austria Maria Theresa. Her Dutch Wikipedia article is here.
Posted to Foro Dinastias by Katyusha on 1 June 2010; darkness added by gogm.
Maria Annunziata's bodice looks like a scaled up version of the slashed balloon sleeves of the 1620s-1630s. Her dress has a natural waistline announced by a waist band and bow while herbodice has a square neckline and supports some large sleeves.