pok-radbundit

122 Notes on the genus Hedychium J. Konig (Zingiberaceae) known for Thailand The Journal of the Royal Institute of Thailand Vol. 33 No. 3 Jul.-Sep. 2008 .. 5. H. coronarium J. K nig in Retz., Obs. 3 (1783) 73. Type : K nig s.n. (holotype C) This beautiful species was first described in 1783. It was stated to be native to Myanmar (Holtumn, 1971). The plant is widely cultivated throughout tropical countries. H. coronarium J. K nig can be easily recognized with its large imbricate bracts and large white fragrant flowers with broad labellum and staminodes. Two varieties were recognized for Thailand, both of which are commonly cultivated as a garden plant. H. coronarium var. chrysoleucum [Fig. 7] could be easily distinguished from H. coronarium var. coronarium [Figs. 6] by its white labellum with large yellow patch in the center. The latter variety is cultivated throughout northern and northeastern regions of Thailand. 6. H. ellipticum Buch.-Ham. ex Sm. in Reeds, cyclop 17 (1811) 2. Type: to be selected This species is distributed from the Himalaya to northern Myanmar. In Thailand, it is common in high altitude mountains in northern and northeastern Thailand, especially on Doi Chiang Dao (Changwat Chiang Mai), Phu Hin Rong-kla (Changwat Phitsanulok) and Phu Kradueng (Changwat Loei). The plant can be easily recognized by its eccentric inflorescence, imbricate and glabrous 1-flowered bracts, and the white laceolate labellum with an emarginate apex. [Fig. 8] 7. H. flavescens Carey ex Rosc., Monandr. Pl. Sci.tam. t. 50 (1825). Type: to be checked This species is related to H. coronarium J. Konig, but differs by its creamy yellow flowers with an orange patch at base, hairy ovary, and longer stamens (sub-equaling the labellum). It is also widely cultivated as ornamental plant. The plant is closely allied to H. flavum Roxb. However, the latter has glabrous leaves (on both sides), wholly yellow labellum, and the longer-than-wide labellum. [Fig. 9] 8. H. forrestii Diels, Not. Roy. Bot. Gard. Edinb. 5 (1912) 304. Type: G. Forrest 4812, China, Western Yunnan, Tali-valley This species is distributed from northern Myanmar, southern China, northern Thailand, Laos, to northern Vietnam. In Thailand, it can be found in evergreen forests at Khun Yuam (Changwat Mae Hong Son) and Phu Kha (Changwat Nan). The Thai specimens showed the following distinguishing characters: inflores- cence cylindric, rachis pubescent; bracts narrowly ovate (1.5-1.8 cm wide), pilose, 2-3 flowers per bract, margin incurved; flower white, calyx tube shorter than bracts, lateral staminodes oblong to elliptic ( ca. 3 by 1.5 cm), and labellum subor- bicular ( ca. 3 cm wide), apex 2- cleft. [Fig. 10] 9. H. gardnerianum Sheppard ex Ker.-Gawl., Bot. Reg. 9: t.774 (1824). Type: to be selected This is a himalayan species, distributed from India, Nepal, Myanmar to Thailand. In Thailand, this species can be found in evergreen forests at an altitude of ca. 1,600 m at Doi Suthep-Pui, Doi Ang Khang (Changwat Chiang Mai), Phu Luang, Phu Ruea, and Phu Kradueng (Changwat Loei). The plant is rather large in habit. The in- florescences are also quite large. This species can be recognized by the following characters: leaves glabrous on upper surface, long hairy on lower surface; ligule oblong, hairy, apex round; spike 20-30 cm long, bracts folded, 4-6 flowers per ..