General:
Somewhat succulent, perennial herb from a rhizome; stems ascending or climbing, 0.5-2 m long, hollow, strongly angled, 3-7 mm wide, sparsely hairy to nearly glabrous.
Leaves:
Alternate, pinnately compound; leaflets 16 to 26, lanceolate to oblong, blunt or narrowed abruptly to a tiny point, 2-6 cm long; tendrils well developed, grasping; stipules broad, sharply toothed, about 1/2 the length of the leaflets.
Flowers:
Inflorescence an axillary, long-stalked, dense, one-sided raceme of 7 to 20 pea-like flowers; corollas yellowish to reddish-purple, 12-18 mm long; calyces 1/2 the length of the corollas, the upper teeth to merely 1 mm long, the lowest one nearly as long as the tube.
Fruits:
Pods, 3-5 cm long, oblong, glabrous, blackened when dry; seeds several, black.