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''Roscoea tibetica'' is a perennial herbaceous plant native to the mountains of China, being found in Tibet, Sichuan and Yunnan.〔 The species formerly included plants found in Bhutan; in 2000, these were separated into a new species, ''Roscoea bhutanica''.〔 Most members of the ginger family (Zingiberaceae), to which it belongs, are tropical, but ''R. tibetica'', like other species of ''Roscoea'', grows in much colder mountainous regions.〔 ''R. tibetica'' is sometimes grown as an ornamental plant in gardens.〔 ==Description== ''Roscoea tibetica'' is a perennial herbaceous plant. Like all members of the genus ''Roscoea'', it dies back each year to a short vertical rhizome, to which are attached the tuberous roots. When growth begins again, "pseudostems" are produced: structures which resemble stems but are actually formed from the tightly wrapped bases (sheaths) of its leaves.〔 ''R. tibetica'' is one of the smaller members of the genus; plants are 5–15 cm tall, with one to three leaves, which have blades 2–6 cm long by 1–2.5 cm wide. The blade is more-or-less hairy; more so when young. There is a very small ligule, extending to about 0.5 mm, at the junction of the leaf sheath and blade.〔 In its native habitats, ''R. tibetica'' flowers between June and July. The stem (peduncle) of the flower spike is hidden by the leaf sheaths. Bracts some 2.2–4 cm long enclose the flowers, which are purple or violet and appear just above the leaves.〔 Each flower has the typical structure for ''Roscoea'' (see the diagrams in that article). There is a tube-shaped outer calyx, brown-spotted and 3–4 cm long with a three-toothed apex. Next the three petals (the corolla) form a tube which is longer than the calyx at 4–5 cm and terminates in three lobes, a narrow upright central lobe, about 1.5–1.7 cm long, forming a hood, and two side lobes, each 1.5–1.8 cm long by 4–5 mm wide. Inside the petals are structures formed from four sterile stamens (staminodes): two lateral staminodes form what appear to be upright petals, 1–1.3 cm long; two central staminodes are fused to form a lip or labellum, about 1.4–2.5 cm by 0.8–1.8 cm, which is divided into two lobes for more than half its length.〔〔 The single functional stamen has a cream anther, about 5–6 mm long, with 3–7 mm long spurs formed from the connective tissue between the two capsules of the anther. The cylinder-shaped ovary is about 1.5 cm long.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Roscoea tibetica」の詳細全文を読む スポンサード リンク
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