黄毛黧豆 huang mao li dou

Twining vines. Stems glabrous or with dense short pale adpressed hairs. Leaves 14-30(-40) cm; petiole 6-11 cm; stipels 2-5 mm, robust; leaflets thickly papery or almost leath­ery, adaxially sparsely or densely hairy with hairs denser on veins, abaxially densely hairy with hairs sparser on veins, rarely glabrous on both sides, lateral veins 5-7 pairs, prominent and conspicuous, straight and running into margin; terminal leaflet rhombic or sometimes rhombic-obovate or broadly ovate, 7-14 × 5.6-11(-13) cm, base broadly cuneate to rounded, apex acute or slightly acuminate; lateral leaflets 7-14 × 4-9 cm, width ratio of abaxial to adaxial halves 2-3:1, base on abaxial side truncate. Inflorescence axillary, 18-41 cm, with usually more than 12 flowering nodes always clustered in upper 2/3 of inflo­rescence; lower part of inflorescence axis with many bracts or their scars; bracts and bracteoles persistent at flowering and often fruiting time, hairy, bracts obovate to lanceolate or linear-lanceolate; pedicels 4-7 mm, densely short spreading hairy and often with longer fine bristles. Calyx densely clothed with soft hairs and yellow-brown irritant bristles; tube 4-7 × 7-10 mm; lateral 2 lobes 2-4 mm, lowest 5-6 mm. Corolla deep purple; standard 1.6-2.3 cm; wings 2.5-3.3 cm × 6-8 mm; keel 2.5-4.3 cm. Legume linear, not or slightly swollen around seeds, straight or slightly downcurved, 6-9 × 1.2-1.6 cm, fleshy, clothed with dark brown irritant hairs. Seeds 3-6, brown or black, usually with pinkish brown marks, ellipsoidal, ca. 9 × 6 mm, ca. 4 mm thick; hilum ca. 5 mm.

Forests, grasslands, roadsides, by rivers; 600-2000 m. Guang­dong, Hainan, Yunnan [Laos, Myanmar, Thailand, Vietnam].

This species is extremely similar to Mucuna pruriens and is only distinguished by the thickly textured robust-veined ovate-rhombic leaf­lets with indumentum abaxially conspicuously sparser on the veins than on the leaf surface, the lower part of the inflorescence with many flow­erless nodes with scars or persistent bracts, and the almost straight leg­ume.