Scrambling perennial; stems glabrous, somewhat angled, broadly winged. Lvs glabrous; tendril branched in upper lvs, sometimes reduced and simple in lower lvs; leaflets in 1 pair, narrowly to broadly elliptic, acute to acuminate, 30-100-(120) mm long; veins parallel; stipules ovate-lanceolate with 1-(2) basal lobes, usually c. as wide as or wider than stem, but at least 1/2 as wide ((3)-5-15 mm wide), 15-35 mm long. Infl. > lvs, (4)-8-14-flowered; pedicels 5-12 mm long. Calyx glabrous, slightly or not gibbous at base; calyx teeth somewhat unequal, triangular; lower teeth = or > tube; upper teeth shorter. Corolla usually magenta or purple-pink, rarely white, (15)-20-30 mm long. Pod glabrous, light brown, 10-15-seeded, 60-110 mm long; seeds reddish brown, reticulate-rugose; hilum ⅕-⅓ of circumference.