Pelargonium zonale flowers

This close-up view of Pelargonium zonale flowers shows the shape difference between the three lower (anterior) and two upper (posterior) petals clearly.

The opposite positioning of the two petal groupings emphasises the zygomorphic or laterally symmetric corolla structure, as opposed to Geranium flowers that are actinomorphic or radially symmetric. The faint vein markings upon the petals are more distinct on the upper ones. Tiny purplish styles with their five curving stigma branches are visible in the photo. So are the short, pointed sepals and the long flower pedicels.