Herbs perennial, from rhizome, glabrous or pubescent. Stems angled, sprawling or climbing, basally branched 0–3 times, 4–10 dm. Leaves 6–18 cm; tendrils well developed; stipules lanceolate to linear, 10–20 × 2–10 mm, much smaller than distal leaflets (less than 1/4 width of distal leaflets); leaflets 8–14, scattered, blades ovate to lanceolate, 25–70 × 10–35 mm, surfaces glabrous or pubescent. Inflorescences 5–20-flowered, 6–20 cm. Flowers 10–15 mm; calyx lobes unequal, lateral lobes linear-triangular or lanceolate, shorter to longer than tube; corolla blue-purple to rose, banner erect, blade equal to claw, wings equal to keel; ovary glabrous or pubescent. Legumes 20–50 × 3–7 mm.

Distribution

North America.

Discussion

Varieties 3 (3 in the flora).

Selected References

None.

Lower Taxa

Lathyrus venosus var. arkansanus, Lathyrus venosus var. intonsus, Lathyrus venosus var. venosus

Key

1	Herbs sparsely to densely pubescent.	Lathyrus venosus var. intonsus
1	Herbs glabrous.	> 2
2	Calyces: lateral lobes linear-triangular, equal to or shorter than tubes.	Lathyrus venosus var. venosus
2	Calyces: lateral lobes lanceolate, longer than tubes.	Lathyrus venosus var. arkansanus