This Polygala myrtifolia var. myrtifolia flower spreads its two clawed, wing-like sepals, angled slightly forward. These are important parts of the floral presence, although they aren’t petals.
The keel petal low on the right is broadly up-curving, ending in the typical Polygala crest, here comprising a spreading bunch of stiff white hairs. The lateral petals are small (Manning, 2007; Bean and Johns, 2005; Coates Palgrave, 2002; iNaturalist).