Mucuna
Fam. Pl. 2: 325, 579. (as Mukuna)s. 1763, name and orthography conserved
Vines, annual or perennial, herbaceous or woody, unarmed. Stems trailing or climbing, pubescent. Leaves alternate, odd-pinnate; stipules present, lanceolate; petiolate; leaflets 3, stipels present, blade margins entire, surfaces pubescent. Inflorescences 10–40-flowered, axillary, racemes or umbelliform, pendent; bracts present, caducous. Flowers papilionaceous; calyx 2-lipped, lobes 5, pubescent; corolla white, yellow, or purple, 30–65 mm; stamens 10, diadelphous; anthers dorsifixed; ovary pubescent. Fruits legumes, pendent, pedicellate, brown, oblong, compressed between seeds, dehiscent, pubescent, often with stinging hairs, ridges longitudinal or transverse. Seeds 1–6, black to brown or white, 1–2 cm diam., spherical to oblong, smooth; hilum lateral. x = 11.
Distribution
se United States, Mexico, West Indies, Central America, South America, Asia, Africa, Pacific Islands (Hawaii), Australia.
Discussion
Species ca. 100 (2 in the flora).
Pending resolution of generic relationships, we follow G. P. Lewis et al. (2005) in treating Mucuna in a broad sense to encompass Stizolobium. The status of putative cultigens, such as M. aterrima (Piper & Tracy) Holland and M. deeringiana (treated here as a synonym of M. pruriens), needs further study. Phylogenetic studies are also needed to resolve issues in species circumscription and the proper application of names, particularly for extralimital taxa.
In addition to the taxa treated below, some species of Mucuna collected from tropical Asia were grown experimentally at the United States Department of Agriculture Experiment Station in Biloxi, Mississippi. These include M. aterrima (= M. pruriens according to R. A. Howard 1974–1989, vol. 4), Stizolobium cinereum Piper & Tracy (no name yet available in Mucuna), M. hassjoo (Piper & Tracy) Mansfeld (= M. pruriens var. utilis according to V. A. Funk et al. 2007), M. lyonii Merrill, M. nivea (Roxburgh) de Candolle ex Wight & Arnott, M. pachylobia Rock, M. stans Welwitsch ex Baker, and M. velutina Hasskarl. There is no evidence that these taxa have escaped.
Selected References
None.
Lower Taxa
Key
| 1 | Legumes 5–9 cm, transverse ridges absent; hilum to 1/4 circumference of seeds, elevated; inflorescences racemes; terminal leaflet blades rhombic-ovate. | Mucuna pruriens |
| 1 | Legumes 9–12(–16) cm, transverse ridges conspicuous; hilum nearly circling seeds, not elevated; inflorescences umbelliform; terminal leaflet blades ovate. | Mucuna sloanei |