Description from Flora of China
Herbs or shrubs, erect, climbing or prostrate, sometimes with carrotlike woody rhizomes. Leaves pinnately 3-foliolate, subdigitate, or 1-foliolate; stipules basifixed; stipels present. Racemes axillary or terminal, sometimes subumbellate, or flowers solitary, axillary. Calyx 5-toothed, 2-lipped, upper lip entire or bifid, lower lip 3-toothed. Corolla white or purple; petals clawed; standard suborbicular, often with inflexed auricles and appendages at base; wings obovate or oblong, ± adherent to keel; keel incurved, often beaked but not twisted. Vexillary stamen free, remainder connate into an open sheath; anthers uniform. Ovary 3-12-ovuled; disk present; style swollen and ± twisted toward base or narrowed from base to tip, glabrous or shortly pubescent all over, or with a ring of hairs around terminal capitate stigma. Legumes straight or arcuate, flattened, not septate. Seeds ± flattened, arillate or strophiolate; hilum short, usually central.
About 60 species: distributed in Africa and Asia; four species in China.
(Authors: Wu Delin (吴德邻 Wu Te-lin); Mats Thulin)