MUCUNA ADANS. (LEGUMINOSAE) IN THAILAND (C.M. WILMOT-DEAR)
bracts or scars in lower (flowerless) part and bracts soon caducous; fruit in M. bracteata is also never “S-shaped”. M. gracilipes is vegetatively indistinguishable from M. pruriens but with much larger, two coloured flowers.
11a. var. pruriens. Wilmot-Dear, Kew Bull. 47: 235 & Fig. 10 A–H. 1992. Figs. 2 S, 5 A–H.
Stems and petioles glabrous or with sparse, fine, adpressed or spreading, pale hairs and often darker bristles. Terminal leaflet 3–16 cm long, elliptic to rhombic-ovate, length/ width ratio 1.5–1.75:1, apex acute or shortly mucronate, lateral leaflets not markedly larger; thin-chartaceous or membranous , rarely glabrous, usually with hairs like those on the stem, less sparse below especially on veins. Inflorescence axis and pedicels with dense, fine, adpressed, silvery, silky hairs and often also sparse red bristles; bracts and bracteoles small, soon caducous, seen only in young bud stage, bracts narrowly ovate or linear-ovate, 6–10 by 2–3 mm with a distinct acumen often comprising S length; bracteoles of similar length but narrower. Calyx with dense silky hairs and bristles like the pedicels; lowest lobe relatively long and narrow 6–10 by 2–3 mm, lateral lobes broadly triangular, 2–4 by 1.5–3.5 mm. Corolla purple but keel lighter than wings; standard 1.6–2.5 cm long, keel 3–4(–4.5) cm long. Fruit narrowly linear-oblong, usually distinctly curved often into “S-shape”, up to 1 cm wide, with dense, irritant, red-gold or brownish caducous bristles completely concealing surface. Seeds fawnish-brown; aril orange.
Thailand.— NORTHERN: Mae Hong Son, Chiang Mai, Chiang Rai, Lampang, Lamphun, Phrae [Franck 1153 (C); ibid, Maxwell 91–857 (E, GH)]; Sukhothai, Phitsanulok; NORTHEASTERN: Nong Khai , Koyama et al.T. 31145 (BKF); EASTERN: Buri Ram, Phengkhlai et al. 3410 (BKF); SOUTHWESTERN: Uthai Thani, Kanchanaburi [Ban Kao, Larsen 8183 (C)], Ratchaburi, Prachuap Khiri Khan; CENTRAL: Lop Buri, Mitsuta et al. 38201 (BKF), Saraburi; SOUTHEASTERN: Chanthaburi; PENINSULAR: Songkhla.
Distribution.— Very widely distributed: tropical Africa, Madagascar, Asia, tropical America.
Ecology.— Dry mixed deciduous or bamboo forest and forest edges, thickets, disturbed areas (hedges, roadsides); sea level–1100 m alt.
Conservation Assessment.— Least concern.
Notes.— Over 40 collections of this common and widespread variety have been seen from Thailand (24 since 1992, of which those cited represent additional locality records). The distinction from var. hirsuta is not always clear (see below) unless the diagnostic acuminate bracts and bracteoles are present. Specimens with straight fruits are distinguishable from M. bracteata by inflorescence characters (see above under whole species) and the fruit in M. bracteata is often broader (to 1.5 cm broad).
11b. var. hirsuta (Wight &Arn.)Wilmot-Dear, Kew Bull. 42: 44 & Fig. 4. 1987 & Kew Bull. 47: 218 & Fig 9 F–G. 1992.—M. hirsuta Wight &Arn., Prod. Fl. Ind. Orient. 1(2): 254. 1834. Type: India, W Peninsular [ ight 750 (holotype K!; isotype E!)].
Stems, petioles, inflorescence axis and pedicels with distinctly orange-brown indumentum of long, spreading, somewhat crisped hairs. Terminal leaflet always rhombic- ovate, often broadly rounded at apex (extreme tip acute), rarely over 12 cm long, rather