High climbing woody vines. Leaves pinnate trifoliolate, the lateral leaflets oblique; stipels scale-like; stipules often caducous. Inflorescences axillary racemes, the peduncles often elongate and the pedicels subumbellate, at least in bud, bracts often subfoliaceous, enclosing the bud, caducous; pedicels arising in 2's and 3's on an expanded portion of the peduncle. Flowers showy, the calyx campanulate, often with irritating hairs, the upper teeth connate, the lower 3 usually unequal; corolla with the standard shorter than the wings, the wings with margins basally ciliate, the keel narrow, apically falcate and indurate; stamens diadelphous, the upper stamen free, the filaments alternately thick and thin, long and short, the anthers sometimes pilose; ovary tomentose, the short stipe surrounded by a glandular disc, the style slender, glabrous or pubescent, the stigma capitate, sometimes of a tuft of hairs. Legume oblong, thick or flattened, the margins often winged, undulate between the seeds and somewhat compressed laterally between the seeds, the surface sometimes lamellate with parallel or irregular raised lamellae which may form elongate enations, mostly densely covered with stiff irritating hairs, tardily dehiscent; seeds flat or convex, discoid, the hilum narrow around more than 1/2 the periphery.
