THAI FOREST BULLETIN (BOTANY) 36
uncertain], Sing Buri [Suphi Ban, Gentry et al. 66475 (L, MO)]; SOUTHEASTERN: Sa Kaeo [ ilkie et al. PW 416a (E)], Chon Buri, Chanthaburi.
Distribution.— E Himalayas (Sikkim, Nepal, NE India), Burma,Vietnam, China (SW, S & Taiwan), S. Japan (Kyushu & Ryukyu Is.)
Ecology. — Evergreen or mixed forest, clearings and forest edges, often by rivers; 600–1600 m alt.
Conservation Status Assessment.— Least concern.
Notes.— M. macrocarpa is widespread and frequently collected (ca 40 collections seen from Thailand, 25 since 1992 of which those cited here represent additional locality records). It is distinguishable from all other Thai taxa by the pubescent apical margin of the standard and wing petals and from all except the rare and local M. thailandica by its large, woody, linear-oblong pod and the absence of stipels. M. thailandica is easily distinguished from it by much larger greenish-white flowers and larger calyx with longer lobes but easily confused in fruit, differing only in possessing leaflets which are always early-glabrescent, terminal leaflet which is usually slightly relatively wider, lateral leaflets less markedly asymmetrical and fruits usually slightly longer. Sterile material with red-brown pubescence is sometimes confused with M. oligoplax or M. monosperma (q.v.).
2. Mucuna thailandica Niyomdham & Wilmot-Dear, Kew Bull. 47: 211 & Fig 2. 1992. Type: Thailand. Northern: Chiang Mai [Doi Inthanon, 1 March 1978, Niyomdham 5 (holotype BKF!, isotype K!)]. Fig. 1 S–T.
Woody climber (10–) 25– 40 m, very similar to M. macrocarpa; stems, petioles and young leaflets with sparse, pale adpressed hairs but leaflets soon glabrescent. Leaves always fairly large with terminal leaflet 9.5–14 cm, elliptic, length/width ratio only 1.5–1.75:1, apex acuminate, lateral veins (4–)5(–6) pairs; lateral leaflets only moderately asymmetrical with ratio of abaxial to adaxial halves 1.5–1.75:1, base of abaxial half rounded or truncate; thin-chartaceous or thin-coriaceous; stipels absent. Inflorescences from old wood, unbranched but several axes from same node, 10–50 cm, pubescent like M. macrocarpa; ultimate branchlets usually knob-like, rarely lengthened to ca 1.5 cm; pedicels (1.5–) 2–3 cm; bracts and bracteoles ovate-elliptic, acute, ca 7 by 5 mm, very early caducous. Calyx pubescent like the axis and with abundant fine orange bristles, tube very wide, 1 by 2.5 cm, lowest lobe 10–13 by ca 6 mm, laterals broadly triangular, acute or abruptly acuminate, 5–8 by 5–8 mm. Corolla greenish-white, extremely large, standard 4.5–5.5 cm long, wing relatively narrow 7–7.5 by 1.6–2.3 cm, keel 7.5–8.5 cm long. Fruit and seeds like those of M. macrocarpa but fruit slightly larger 47–60 by 4–4.5 cm, not or slightly constricted between seeds.
Thailand.— NORTHERN: Chiang Mai [Doi Inthanon, 1 March 1978, Niyomdham 5 (holotype BKF!, isotype K!); idem, Niyomdham 5266 & 5287 (BKF); idem, Konta et al. 4238 (BKF); idem, Koyama et al. 44203 (BKF); idem, Nagamasu T.50092 (BKF); idem, Phengklai et al. 11001 & 11026 (BKF); Pooma 1394 (BKF); idem, Smitinand 90–93 (BKF)].
Distribution.— Endemic (known only from Doi Inthanon)
Ecology.— Montane forest, gallery forest often in clearings and near streams, 1000– 2400 m alt.