Description from Flora of China
Twining herbs or shrubs. Roots sometimes tuberous. Stipules sometimes produced below point of insertion. Leaves pinnately 3-foliolate; leaflets large, stipellate, ovate or rhomboid, entire or sinuately lobed. Inflorescences axillary, racemose or paniculate with an elongated peduncle, or several racemes aggregated at tip of branchlets. Bracts usually small or narrow, very caducous; bracteoles small, subpersistent or minute and caducous. Flowers blue or purplish, usually several flowers clustered at each node of rachis. Calyx campanulate, 2 upper teeth connate into entire or bifid lip. Corolla exceeding calyx; standard with 2 inflexed auricles; wings narrowly oblong or obovate-falcate, often adherent to middle of keel; keel sometimes beaked, subequal to wings. Vexillary stamen free at base, connate in middle with others, rarely quite free; anthers uniform. Ovary subsessile, many ovuled; style filiform, inflexed above; stigma small, capitate. Legumes linear or cylindric, continuous within or filled or septate between seeds. Seeds compressed, suborbicular or transversely oblong.
About 20 species: distributed in tropical and E Asia; ten species (three endemic) in China.
(Authors: Wu Delin (吴德邻 Wu Te-lin); Mats Thulin)