Annual, Herb s, Taproot present, Nodules present, Stems erect or ascending, Stems or branches arching, spreading or decumbent, Stems less than 1 m tall, Climbing by tendrils, Stems solid, Stems or young twigs glabrous or sparsely glabrate, Leaves alternate, Leaves petiolate, Stipules conspicuous, Stipules green, triangulate to lanceolate or foliaceous, Stipules persistent, Stipules free, Leaves compound, Leaves even pinnate, Leaf or leaflet margins entire, Leaflets opposite, Leaflets 2, Leaves glabrous or nearly so, Flowers solitary in axils, or appearing solitary, Inflorescence axillary, Bracts very small, absent or caducous, Flowers zygomorphic, Calyx 5-lobed, Calyx glabrous, Petals separate, Corolla papilionaceous, Petals clawed, Petals blue, lavander to purple, or violet, Banner petal ovoid or obovate, Banner petal suborbicular, broadly rounded, Wing petals narrow, oblanceolate to oblong, Wing petals auriculate, Wing tips obtuse or rounded, Keel tips obtuse or rounded, not beaked, S tamens 9-10, Stamens diadelphous, 9 united, 1 free, Filaments glabrous, Style flattened, Style hairy, Style hairy on one side only, Style persistent in fruit, Fruit a legume, Fruit unilocular, Fruit freely dehiscent, Fruit elongate, straight, Fruit exserted from calyx, Valves twisting or coiling after dehiscence, Fruit glabrous or glabrate, Fruit hairy, Fruit 3-10 seeded, Fruit 11-many seeded, Seeds ovoid to rounded in outline, Seed surface smooth, Seeds olive, brown, or black.
Erect annual, 10-35 cm tall, stem glabrous or pubescent. Leaf pinnately compound, leaflets 2, 1.5-6.0 cm long, 1-7 mm broad, linear-lanceolate, acute, glabrous; stipules 5-9 mm long, lanceolate, semisagittate. Flower solitary axillary, pedicel short. Calyx 4-5 mm, teeth equal, 1- ½ times as long as the tube. Corolla lilac rarely white. Vexillum 7-9 mm long. Fruit 3.0-5.0 cm long, 4-5 mm broad, linear, glabrous or pubescent, 7-11-seeded.