Erect shrub to 2 m. Leaves unifoliolate, subopposite to opposite on flowering branches, lanceolate-elliptic. Flowers solitary, large, buds leaf-like, keel rostrate, calyx lobes much longer than tube, upper lobes broader and falcate, lower lobe very narrow, shorter than the others. Pods large, obliquely oblong, upper margin asymmetrically convex.