Vines, perennial, herbaceous or ± woody, unarmed. Stems climbing, twining, or prostrate, pubescent to glabrate. Leaves alternate, odd-pinnate; stipules present, usually caducous; petiolate; leaflets 5(or 7), stipels absent, blade margins entire, surfaces puberulent, glabrate, or glabrous. Inflorescences 1–8-flowered, axillary, fascicles or racemes [panicles]; bracts present, stipulelike; bracteoles usually absent. Flowers papilionaceous; calyx nearly actinomorphic, campanulate, lobes 5; corolla yellow [white or purplish]; stamens 10, monadelphous, filament tube splitting adaxially at maturity; anthers dorsifixed. Fruits loments, stipitate, flattened, lanceoloid, segments breaking apart, individual ones indehiscent, pubescent, glabrate, or glabrescent; segments 2–4, proximal 1–4 segments fertile, distal segment sterile, flat, winglike. Seeds 1–4, reddish brown, laterally compressed, reniform, sublustrous; hilum relatively small, circular.

Distribution

sw United States, Mexico, Central America, South America, warm-temperate and tropical regions.

Discussion

Species 14 (3 in the flora).

Selected References

None.

Lower Taxa

Nissolia platycalyx, Nissolia schottii, Nissolia wislizeni

Key

1	Fruits with sterile segment 6–11 mm, fertile segments 7–10 mm; stems prostrate; leaf axis recurved; leaflets usually folded when dry.	Nissolia wislizeni
1	Fruits with sterile segment 10–30 mm, fertile segments 4–7 mm; stems climbing or twining; leaf axis ± straight; leaflets usually not folded when dry.	> 2
2	Corollas 14–20 mm; pedicels 9–11 mm; calyx tube 4.5–6 × 4–5 mm, lobes 1.5–4.5 mm; leaflets 5 or 7.	Nissolia platycalyx
2	Corollas (8–)10–12 mm; pedicels 5–7 mm; calyx tube (2–)3–4 × 2–3 mm, lobes 2–4 mm; leaflets 5.	Nissolia schottii