Standard obovate, emarginate, shortly clawed; wings oblong, shortly clawed, finely denticulate above, marked with a few small pockets; keel obtuse, spurred, finely denticulate above.
Fruit many-jointed, linear, compressed, coiled into a ring or a spiral, minutely roughened on the margins; articles numerous, separating, the nerve persistent after they have fallen.
Stamens all joined, the tube split completely unilaterally or for half its length to form 2 bundles of 5, or with the vexillary filament free; anthers uniform.
Ovary linear, falcate, subsessile, many-ovuled; style curved, inflexed; stigma small, terminal.
Leaves alternate, sensitive, paripinnate; stipules membranous, spurred; stipels absent.
Inflorescences umbel-like racemes, 1–4-flowered; bracts and bracteoles small, thin.
Erect or spreading annual herbs, mostly branched and tufted.
Seeds broadly irregularly reniform; hilum minute, eccentric.
Calyx deciduous, 2-lipped; lips almost entire.
Flowers small, yellow.