Erect shrublet to 1.2 m. Leaves unifoliolate, subopposite to opposite on flowering branches, broadly elliptic to orbicular, acuminate. Flowers solitary, sometimes to 4, large, keel rostrate, calyx lobes triangular, shorter than tube, upper lobes broader than the others. Pods short-stipitate, obliquely lanceolate, upper suture broadly winged.