Widely spreading, prostrate or sub-erect, undershrub; stem and branches prickly, densely clothed with deflexed bristles; leaves digitate, bipinnate, pinnae usually 2 pairs, leaflets 12-20 pairs, small, sessile, ligulate, linear-oblong, glabrous, subcoriaceous, very sensitive; stipules linear-lanceolate; flowers in small, pink-purple, peduncled, globose, axillary heads, pink-purple; calyx campanulate, shortly toothed; petals-4, ovate- oblong, obtuse, connate at the base; stamens twice the number of petals, much exerted, filaments filiform, free, anthers minute; ovary stalked, many ovuled, style filiform, stigma minute, capitate; pods long, flat, membranous, joints 3-5, that separate when ripe, armed with abundant, long, weak, spreading, yellow, prickly bristles on both sutures.