The genus Crotalaria is part of the Fabaceae family, known as the rattlepods. There are more than 600 species of rattlepods on earth. More than 500 of those occur in Africa. Apart from having pretty flowers, many of them are popular with butterflies for the nectar they produce in return for the pollinated that happens unintentionally in the process.
The pale yellow flower photographed at Kaapse Hoop has a prominent calyx, dark on the ovary part with acute tips around the corolla. The standard petal has dark lines on both surfaces. Tiny bracts can be seen on the stem next to flower stalks.