贵州黧豆 gui zhou li dou

Mucuna corvina Gagnepain; M. terrens H. Léveillé.

Large climbing woody vines. Stems with sparse short pale fine spreading hairs when young, later glabrous. Leaves 21-32 cm; petiole 7-14 cm, with sparse or abundant hairs like stem; stipels not persistent; leaflets papery or rather leathery, abax­ially with dense short fine half-adpressed hairs, adaxially gla­brous or with similar but sparse hairs, lateral veins 5-8 pairs, gently curved, often rather closely spaced; terminal leaflet broadly elliptic-ovate or elliptic to slightly obovate or almost rhombic, 11-14 × ca. 8 cm, base rounded or slightly cuneate, apex broadly rounded with abrupt minute acumen; lateral leaf­lets 10-13.5 cm, width ratio of abaxial to adaxial halves 1.6-2:1. Inflorescence on old stem, over 10 cm, with ca. 9 nodes; bracts ± ovate, ca. 2 × 1.5 mm, densely hairy, persistent. Calyx densely adpressed hairy and often with sparse caducous bris­tles; tube 1.1-1.4 × ca. 2 cm; lateral lobes 3-6 mm, lowest 6-10 mm, upper lip indistinct or almost equaling lateral lobes. Corol­la deep purple (possibly sometimes white); standard 3.4-4 cm, margin conspicuously pale pubescent in apical 1/3; wings very narrow, 6-7 × 1.5-2 cm, margin pubescent like standard in api­cal 1/3; keel 7.2-7.7 × ca. 1 cm. Legume linear, slightly curved, 47-60 × 3-5 cm, ca. 1.5 cm thick, woody, margin not or only slightly constricted between seeds (segments rectangular) but internal septa visible as transverse grooves, apex acute, base without narrow neck, densely minute spreading hairy, surface with several irregular undulating interrupted longitudinal woody ridges, each margin thickened into 2 ridges up to 1 mm high with a median groove running along suture; septum thin inside, ± woody. Seeds ca. 16, dull black, oblong-disk-shaped; hilum ca. 1/3 length of seed circumference; strophiole ca. 4 mm wide.

● 1000-1500 m. Guizhou (Anshun).

Mucuna bodinieri is presumably rare, as it is known from only seven collections.

This species is distinctive in having leaflets broadly rounded, shortly acuminate, and densely softly pale hairy; stipels not persistent; large purple flowers with pubescent petal apices; and a large linear legume with rectangular segments. Mucuna macrocarpa has similar flowers and fruit but differs in its acute or acuminate leaflets with red-brown, often sparse, indumentum and often fewer veins.

The syntypes of Mucuna bodinieri and M. terrens were collected from adjacent localities only ca. 10 km apart. Those of M. bodinieri lack fruit, but the ovary is similar; and they otherwise differ from those of M. terrens only in having the lowest calyx lobe longer and slightly broader and the leaflets thinner textured with a mucronate rather than shortly acuminate apex.