Herbs, prostrate or decumbent, much-branched, to 10 dm. Stems glabrous. Leaves 2.5–6.3 cm; stipules persistent, 2.5–7 mm, without winged margin at base, glabrous; petiole 2–5 mm; pinnae 4–9 pairs; nec­tary present or absent, sessile, cra­teriform, interpinnal between proximal pair of pinnae; leaflets 30–44, blades 2–4.5(–6.8) mm, venation obscure except for eccentric mid­vein, surfaces glabrous. Peduncles 0.6–2 cm, 0.8–2.5 cm in fruit. Heads 1 per axil, 4–10-flowered, all bisexual. Flowers: stamens 5; style exserted beyond stamens. Legumes dark brown, straight, linear, regularly constricted between seeds, edges scalloped, dehiscent along both sutures, 4–7.5 cm × 2.5–3 mm, apex acute to apiculate with beak 1–3 mm. Seeds inserted longitu­dinally. 2n = 28.

Phenology: Flowering May–Aug, fruiting Jun–Sep.
Habitat: Rich black­land prairies and woodlands, roadsides, uncultivated fields, waste areas.
Elevation: 150–300 m.

Distribution

• Generated Map
• Legacy Map

Kans., Mo., Okla., Tex.

Discussion

In Desmanthus leptolobus, the scalloped edges of the legume where it is constricted between the seeds and the longitudinal insertion of the seeds are diagnostic. The Missouri records are from along railroad tracks and likely represent introductions.

Selected References

None.

Lower Taxa

None.