Polygala virgata var. speciosa flower

The flashy flowers of Polygala virgata var. speciosa have lifted their floral pairs of petaloid wing sepals high. The sepals are obliquely rounded, pale pink purple with conspicuous venation showing against the light.

The keel crests or modified keels are eye-catching, ample brushes at the tips of the lower petals that are boat-shaped. This is where the insects reach the nectar. Keel crests in Polygala serve to attract pollinators visually as prominent flags, recognised by repetition. They also serve as levers, mechanically facilitating the opening of keels to get easier access to nectar and pollen.

Archimedes wanted a place to stand and a long enough lever for moving the earth. Insects have mastered the same principle, as well as the scale issue, in moving Polygala flower crests. 

Flying insects can also land on the keels; six feet surely performing a landing here more adroitly than two ever could (Manning, 2009; De Kock, et al, 2018: The functional role of the keel crest in Polygala myrtifolia (Polygalaceae). Journal of Botany, vol 118, pp 105-111; iNaturalist).