Description from Flora of China
Herbs, climbing, turning black when dry. Leaves pinnately 3-foliolate, stipellate. Racemes axillary; rachis slender, nodose. Flowers usually clustered at swollen nodes; bracts and bracteoles minute, subulate, caducous or subpersistent. Calyx campanulate, 2-lipped, upper 2 teeth connate into a larger upper lip, apex emarginate or entire, lower lip with 3 teeth, middle tooth longest, lateral 2 shorter. Petals subequal in length or standard shorter, with long or short claws; standard broadly ovate, with inflexed auricles at base; wings oblong or subspatulate, slightly longer than standard, base with long auricle; keel linear, as long as or longer than wings, coiled inward in upper part. Stamens diadelphous; vexillary stamen free; anthers uniform. Ovary shortly stipitate, many ovuled; style filiform, glabrous, upper part coiled inward into 1 or 2 circles; stigma large, peltate-dilated, terminal. Legumes linear-oblong, incurved, compressed, obscurely septate. Seeds quadrate; hilum short, estrophiolate.
Two species: S and SW China, Nepal; two species (one endemic) in China.
(Authors: Chen Dezhao (陈德昭 Chen Te-chao), Zhang Dianxiang (张奠湘); Mats Thulin)