Perennial, Shrubs, Woody throughout, Nodules present, Stems erect or ascending, Stems or branches arching, spreading or decumbent, Stems 1-2 m tall, Trunk or stems armed with thorns, spines or prickles, Stems solid, Stems or young twigs sparsely to densely hairy, Leaves alternate, Leaves petiolate, Stipules inconspicuous, absent, or caducous, Stipules deciduous, Stipules free, Leaves compound, Leaves bipinnate, Leaf or leaflet margins entire, Leaflets opposite, Leaflets 10-many, Leaves glabrous or nearly so, Inflorescences globose heads, capitate or subcapitate, Inflorescence axillary, Bracts very small, absent or caducous, Flowers actinomorphic or somewhat irregular, Calyx 5-lobed, Calyx glabrous, Petals united, valvate, Petals white, Stamens numerous, more than 10, Stamens completely free, separate, Stamens long exserted, Filaments glabrous, Style terete, Fruit a legume, Fruit s tipitate, Fruit unilocular, Fruit freely dehiscent, Fruit tardily or weakly dehiscent, Fruit elongate, straight, Fruit oblong or ellipsoidal, Fruit strongly curved, falcate, bent, or lunate, Fruit exserted from calyx, Fruit glabrous or glabrate, Fruit 3-10 seeded, Seed with elliptical line or depression, pleurogram, Seeds ovoid to rounded in outline, Seed surface smooth, Seeds olive, brown, or black.