Perennial, Shrubs, Woody throughout, Nodules present, Stems or branches arching, spreading or decumbent, Stems less than 1 m tall, Stems 1-2 m tall, Trunk or stems armed with thorns, spines or prickles, Stems solid, Stems or young twigs glabrous or sparsely glabrate, Leaves alternate, Leaves clustered on spurs or fasicles, Leaves petiolate, Extrafloral nectary glands on petiole, Stipules conspicuous, Stipules free, Stipules spinose or bristles, Leaves compound, Leaves bipinnate, Leaf or leaflet margins entire, Leaflets opposite, Lea flets 10-many, Leaves viscid, sticky, 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 stipitate, 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 coriaceous or becoming woody, Fruit exserted from calyx, Fruit compressed between seeds, 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.