Description from Flora of China
Herbs or subshrubs, erect or diffuse. Leaves pinnately 3-foliolate or only 1-foliolate, stipellate. Flower small, 3-6 mm. Panicles or racemes terminal, rarely axillary. Calyx membranous, campanulate, accrescent, 5-lobed; lobes ovate-lanceolate, ca. as long as tube and slightly broader. Corolla ca. as long as calyx or more; standard broad, base attenuate, clawed; wings adherent to keel; keel obtuse. Stamens diadelphous (9+1); anthers uniform. Ovary many ovuled; style linear, incurved; stigma capitate. Legume many jointed, articles folded, reticulate veined, enclosed by calyx.
About 13 species: tropical Asia and Australia; five species (one endemic) in China.
(Authors: Huang Puhua (黄普华 Huang Pu-hwa); Hiroyoshi Ohashi)