All Floras      Advanced Search
FOC Vol. 10 Page 208, 210, 217,218 Login | eFloras Home | Help
FOC | Family List | FOC Vol. 10 | Fabaceae | Mucuna

16. Mucuna pruriens (Linnaeus) Candolle, Prodr. 2: 405. 1825.

刺毛黧豆 ci mao li dou

Semiwoody twining vines. Stems and branchlets slender, with dense long fine hairs and often coarser longer hairs, later glabrous. Leaves up to 46 cm; petiole 8-26 cm, hairy like stem; stipels robust, tapering to tip, 4-5 mm; leaflets papery, adaxially sparsely or abundantly hairy when young, later glabrous, abax­ially clothed with short white silky hairs, lateral veins 5-8 on each side, slender, straight or slightly curved, running into mar­gin; terminal leaflet elliptic or ovate-rhombic, (3-)14-16 × (4.5-)8-10 cm, base broadly cuneate to rounded, apex rounded, acute, or shortly acuminate; lateral leaflets 7-19 cm, width ratio of abaxial to adaxial halves 2-3:1, abaxial half with base ± truncate or rarely cordate. Inflorescence axillary, long and pen­dulous, 15-35 cm, with (2-)5-20 nodes, all in upper 2/3 of inflorescence with no bracts or scars in lower part; pedicels 2-4(-6) mm, densely adpressed hairy and often bristly; bracts and bracteoles linear-lanceolate 6-9 mm, hairy, caducous before flowers open. Calyx with dense soft adpressed pale hairs and often irritant orange bristles; tube ca. 5 × 10 mm; lateral 2 lobes broadly triangular, 2-4 × 1.5-3(-3.5) mm, lowest narrowly tri­angular, 6-10 × 2-3 mm. Corolla deep purple; standard 1.6-2.5 cm, 1/2-2/3 of keel length; wings 2-4 × ca. 1.2 cm, shorter than or subequal to keel; keel 2.8-4.2(-4.5) cm. Legume linear-ob­long and slightly swollen around seeds or misshapen with irreg­ular swellings around seeds, to 9 × 1(-2) cm, ca. 5 mm thick, densely covered with soft pale hairs or orange to brown irritant caducous bristles, margin thickened, surface with or without longitudinal ridges. Seeds 3-6(-8), white to light yellow-brown, orange, brown, or black, sometimes mottled in various colors, elliptic, 0.9-1.78(-2) × 0.4-1.3 cm, (3-)4-10 mm thick; hilum 3-6 mm, ca. 1/8 of seed circumference, with aril forming a raised orange border. Fl. Sep-Jan, fr. Oct-Apr.

Forests, riversides, thickets, tall scrub, roadsides, also cultivated; below 1700 m. Guangdong, Guangxi, Guizhou, Hainan, Hubei, Si­chuan, Taiwan, Yunnan [widely distributed in the tropics].

Mucuna pruriens is distinctive in its small flowers crowded along the upper part of the often very long inflorescence and is easily dis­tinguished from all species, except M. bracteata and M. incurvata, by its ± straight lateral veins running into the leaflet margin and its small fleshy linear fruit.

One flowering specimen of uncertain identity has been seen from Ting Wu Shan, Guangdong (Nan Z. D. 526, MO), which differs from Mucuna pruriens mainly by the extremely long stipels ca. 15 mm.

1 Fruit with orange or brown irritant bristles, to ca. 1 cm wide; seeds uniform in color; terminal leaflet with length 1.5-1.75 × width, lateral leaflets of similar size; calyx often with irritant bristles.   16a var. pruriens
+ Fruit with long pale silky hairs, often misshapen, irregularly swollen around seeds, to 2 mm wide in parts; seeds often mottled or streaked in different colors; terminal leaflet broad, length less than or to 1.5 × width, lateral leaflets often much larger than terminal; calyx without irritant bristles.   16b var. utilis

Lower Taxa


Related Objects  

Annotated Checklist of the Flowering Plants of Nepal  
  • Image/JPEG (KK Shrestha)
  • Image/JPEG

    Flora of China @
    Browse by
    Advanced Search

    Flora of China Home




     |  eFlora Home |  People Search  |  Help  |  ActKey  |  Hu Cards  |  Glossary  |