毛瓣黧豆 mao ban li dou

Type: China. Yunnan: "Jenn-Yeh Hsien, Meng-Ping" [Mengla County, Mengpeng Township], Oct 1936, C. W. Wang 78923 (holotype, PE; isotype, A).

Mucunae macrobotryi similis sed corolla minore ad api­cem omnino glabromarginata, carina breviore 5-5.5 cm longa alas aequante (nec 7.5-9 cm nec quam alis longiore), alis in su­perficie adaxiali pilos conspicuos longos per dimidium basale abundanter dispersos ferentibus et calyce pedunculoque pilos patentes (nec adpressos) ferentibus differt.

Climbing vines. Stems with sparse reddish brown short hairs. Leaves ca. 35 cm; petiole ca. 15 cm with sparse brown short spreading hairs; stipels robust, 4-6 mm; leaflets thinly leathery or papery, glabrous except for occasional hairs on veins abaxially, lateral veins 5 or 6 pairs, strongly curved; termi­nal leaflet elliptic or elliptic-obovate, ca. 14 × 8.5 cm, base rounded, apex with abrupt acumen ca. 1 cm; lateral leaflets ca. 13 cm, width ratio of abaxial to adaxial halves ca. 1.5:1. Inflo­rescence ca. 10 cm, with 4 or 5 nodes spaced throughout length; bracts caducous, not seen; pedicels ca. 1 cm, with abundant golden spreading short hairs. Calyx with dark brown short spreading hairs and red-brown caducous fine long bristles; tube ca. 1 × 1.6-1.8 cm; lobes narrowly triangular, lowest ca. 12 mm and laterals ca. 7 mm, upper lip sometimes longer than laterals. Corolla deep purple (drying brownish); standard ca. 3.2 cm; wings 5-5.5 × ca. 2 cm, ca. equaling keel, inner surface with abundant long fine adpressed pale hairs in basal half. Ovules ca. 3. Mature fruit unknown.

● Dense woodlands near rivers; ca. 800 m. S Yunnan (Mengla).

This new species is Mucuna "sp. C" of Wilmot-Dear (Kew Bull. 39: 50. 1984). Known only from the type gathering, it is unusual in having conspicuous fine long hairs on the inner surface of the corolla wings (as in M. lamellata, which is otherwise very different in its smaller flowers and rhombic leaves). Its general appearance is that of M. macrobotrys, which differs in its mostly smaller leaves, its adpressed indumentum on the peduncles and calyx, and especially in its longer corolla with the keel longer than the wings and its standard and wings pubescent on their apical margins but not hairy on the inner surface.