Rhynchosia minima
Prod. 2: 385. 1825.
Herbs or subshrubs. Stems usually prostrate or twining, rarely ascending, rarely viscid, glabrous, puberulent, or villosulous, hairs silvery or grayish, spreading or reflexed. Leaves trifoliolate; stipules persistent, linear to lanceolate, 1–6 × 1–2 mm, apex acuminate, surfaces puberulent to villosulous; petiole 4–100 mm, glabrous, tomentulose, or villosulous; leaflet blades rhombic-orbiculate, rhombic, subrhombic, or ovate, 30–90 × 5–70 mm, membranous or nearly leathery, gland-dotted, base obtuse to rounded, cuneate, or truncate, apex acuminate to obtuse, surfaces glabrous, puberulent, or sparsely to densely villosulous abaxially, glabrous or finely strigose, villosulous, or puberulent adaxially. Inflorescences racemes, longer than leaves, 2–20 cm. Pedicels 1–5 mm. Flowers: calyx 3–6 mm, puberulent or villosulous, tube 1.5–2 mm, lobes lanceolate, laterals 1.5–4 mm, lengths to 2.5 times tube, adaxials 0.5–1 mm; corolla yellow, veined purple or brown; banner orbiculate-ovate, 4–6 × 3–5 mm, emarginate, puberulent, gland-dotted; wings narrowly oblong, 4.5–5 × 1–2 mm, narrowly gland-dotted, puberulent apically; keel 5–6 × 2–3 mm, glabrous; stamens 5–7 mm. Legumes falcate to oblong-ovoid, compressed, 9–20 × 3–5 mm, glabrous, puberulent, or villosulous. Seeds grayish, brown, black, or mottled, ovoid-reniform, plump, 3–4 × 2–3 mm. 2n = 22.
Phenology: Flowering spring–summer.
Habitat: Disturbed areas, forests, edges, prairies, sand dunes.
Elevation: 0–100 m.
Distribution
Ala., Ark., Fla., La., Miss., Mo., Tex., West Indies, Bermuda, Central America, South America.
Discussion
Rhynchosia minima was recently collected in Alabama after an absence of over 100 years (A. R. Diamond 2015).
Glycine littoralis Vahl ex de Candolle is an illegitimate name that pertains here.
Selected References
None.