Herbs, perennial; root turnip-shaped, small. Stems prostrate, solid, strigulose or hirsute. Leaves: stipules spreading, widely deltate or ovate, 4.5–8 × 2–2.7 mm; petiole 1.7–6 cm, strigose or hirsute; rachis 5–9 mm; sti­pels subulate, 1–5.5 mm; leaflets papery, blades orbiculate, ovate to broadly ovate or obovate, base attenuate or cuneate, apex acute or obtuse, surfaces strigose abaxially, hirtellous adaxially; lateral blades 2–4.3 × 1.6–2.9 cm, sometimes 2-lobed, terminal blades 2.3–4.7 × 1.6–2.8 cm. Inflorescences 14–25 cm (cleistogamous inflorescence over soil, 1.5–2.2 mm, flowers 3.5 mm, corolla whitish), axes adpressed-pilose; tufts of bracts at base of peduncle mostly caducous; extrafloral nectaries inconspicuous at nodes; bracts and bracteoles subulate or lanceolate. Pedicels 0.7–1 mm. Flowers 1 cm; calyx campanulate, 3.5–4.5 mm, hirtellous, calyx lobes as long as tube or longer; corolla salmon-orange; banner orbiculate, 5.5–7.5 × 4.5–6.5 mm; wings oblong-ovate, 5.1–10 × 3.3–6.6 mm; keel 4–8 mm; ovary nectary disc distally even; ovules 6. Legumes pendent, oblong-falcate, 1.6–2.5 × 2.7–3 cm, valves not twisting at dehiscence. Seeds 4 or 5, oblong, 2.9–3 × 2–2.2 mm.

Phenology: Flowering Jul–Sep.
Habitat: Rocky summits, oak forests, savanna-grasslands.
Elevation: 1300–2500 m.

Distribution

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Ariz., N.Mex., Tex., Mexico, Central America.

Discussion

Phaseolus micranthus M. Martens & Galeotti and P. parviflorus Schlechtendal are illegitimate names that pertain here.

Selected References

None.

Lower Taxa

None.