Calobota sericea flowers

The yellow Calobota sericea flower has a large banner flexed back and narrowing at the base. Its two halves meet in a vertical pleat down the centre, the margins arching down from an obtuse angle at the tip where a bent-back protrusion is visible on the flowers in picture.

The keel petal is longer than the wings that angle only slightly away from its sides. The keels in picture are whitish near their tips, possibly from hairs being present (Manning, 2007; Le Roux, et al, 2005; iNaturalist).