General: Perennial herb from a slender rhizome; stems slender, erect, 10-30 cm tall, not winged, glabrous to sparsely short-hairy.
Leaves: Alternate, pinnately compound; leaflets 2 or 4, usually paired but sometimes scattered, linear to broadly oblong, 2-15 cm long, 2-14 mm wide, distinctly veined; tendrils bristle-like, 1-3 mm long; stipules narrow, unequally 2-lobed, less than 1/3 the length of the leaflets.
Flowers: Inflorescence of 2 to 3 pea-like flowers in a leaf axil; corollas pink to bluish, 10-13 mm long, the wings longer than the keel, about equal to the banner, the wing-blade slightly longer than the claw; calyces 6-8 mm long, the teeth narrowly lanceolate, the upper two about equal to or shorter than the lower three, the lowest one only slightly shorter than the tube.
Fruits: Pods, glabrous, 3-4 cm long, 4-7 mm wide; seeds 7 to 12.
