|
''Microtis'' (onion orchids) is a small genus in the orchid family Orchidaceae. == Description == These orchids occur from South China to Japan, Southeast Asia, Australia (except the Northern Territory), New Zealand and certain islands of the Southwest Pacific, in grassland and scrub.〔(Kew World Checklist of Selected Plant Families )〕 They are deciduous, chlorophyllous, sympodial, tuberoid terrestrial orchids with a single, cylindrical leaf that encloses the stem. The tiny flowers are green and arranged in a many-flowered (50 to 100) spiral in a spike or raceme around the erect and tall central stalk. The lowermost flowers are close the exit of the stalk from the sheathing leaf. The dorsal sepal is sharp-pointed and forms a hood over the column. The lateral sepals are oblong and sometimes recurved. The dorsal sepal often keeps the oblong petals out of sight. The lip is ovate-oblong with united basal calli. The lobed lip has a rough, irregular margin. Every flower tends to set seed, after being pollinated by wingless worker ants from the genus ''Iridomyrmex'', attracted by nectar at the base of the lip. This is an exceptional case of pollination by ants, since ants tend to secrete an anti-fungal substance that kills pollen. This doesn't seem to affect ''Microtis'' pollen. ''Microtis'' orchids are often cryptic and difficult to differentiate. ''Microtis unifolia'' seems to have three different groups in New Zealand with different geographical ranges, habitats and flowering times. 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「Microtis (orchid)」の詳細全文を読む スポンサード リンク
|