| 词条 | Pterostylis micromega |
| 释义 |
| name = Swamp greenhood | image = | image_caption = | genus = Pterostylis | species = micromega | authority = Hook.f.[1] | synonyms_ref = [1] | synonyms =
}} Pterostylis micromega, commonly known as the swamp greenhood, is a species of greenhood orchid endemic to New Zealand. Both flowering and non-flowering plants have a rosette of leaves while flowering plants also have a single, relatively large whitish flower with a pointed dorsal sepal. The flower colour and pointed dorsal sepal are unique in New Zealand Pterostylis. DescriptionPterostylis micromega is a terrestrial, perennial, deciduous, herb with an underground tuber and which often grows in loose colonies. Non-flowering plants have a rosette of broad elliptic leaves, each leaf {{convert|35-50|mm|in|sigfig=1|abbr=on}} long with a petiole a further {{convert|5-10|mm|in|sigfig=1|abbr=on}} wide. Flowering plants have a similar rosette at the base of a flowering stem {{convert|150-380|mm|in|sigfig=1|abbr=on}} tall with egg-shaped stem leaves wrapped around it, the highest leaf about as tall as the flower. There is a single, mostly whitish flower with a pale green tinge. The dorsal sepal and petals are fused, forming a hood or "galea" over the column. The dorsal sepal is {{convert|25-40|mm|in|sigfig=1|abbr=on}} long and curves forward with a tapering tip. The lateral sepals are erect, have narrow tips which are higher than the galea and there is a wide gap between them and the galea. The labellum is curved, reddish-brown and protrudes above the sinus between the lateral sepals. Flowering occurs between November and February.[2][3]Taxonomy and namingPterostylis micromega was first formally described in 1853 by Joseph Dalton Hooker and the description was published in Flora Novae-Zelandiae.[1][4] The specific epithet (micromega) is derived from the Ancient Greek words mikros meaning "small" or "little"[5]{{rp|488}} and mega meaning "large".[5]{{rp|834}} Distribution and habitatThe swamp greenhood grows in swampy areas sometimes in colonies of up to fifty. It has been recorded on the North, South and Chatham Islands but its distribution is now much reduced. It has not been observed on Chatham Island since the 1800s but is still present near Waikato, on the Volcanic Plateau, near Wanganui and in the Wairarapa.[2][3] ConservationPterostylis micromega is classed as "threatened and nationally critical" under the New Zealand Threat Classication System.[6]References1. ^1 2 {{cite web|title=Pterostylis micromega|url=http://www.theplantlist.org/tpl1.1/record/kew-170590|publisher=The Plant List|accessdate=3 July 2017}} {{Taxonbar|from=Q15492623}}2. ^1 {{cite web|last1=de Lange|first1=Peter James|title=Pterostylis micromega|url=http://www.nzpcn.org.nz/flora_details.aspx?ID=36|publisher=New Zealand Plant Conservation Network|accessdate=3 July 2017}} 3. ^1 {{cite web|title=Pterostylis micromega|url=http://www.nativeorchids.co.nz/Species/Pterostylis_micromega.html|publisher=New Zealand Native Orchid Group|accessdate=3 July 2017}} 4. ^{{cite book|last1=Hooker|first1=Joseph Dalton|title=Flora Novae-Zelandiae|date=1853|publisher=Lovell Reeve|location=London|page=248|url=https://www.biodiversitylibrary.org/item/54141#page/299/mode/1up|accessdate=3 July 2017}} 5. ^1 {{cite book|last1=Brown|first1=Roland Wilbur|title=The Composition of Scientific Words|date=1956|publisher=Smithsonian Institution Press|location=Washington, D.C.}} 6. ^{{cite web|title=Conservation status of New Zealand indigenous vascular plants, 2012|url=http://www.nzpcn.org.nz/publications/NZTCS-Vascular%20Plants%20-%202013.pdf|publisher=New Zealand Government Department of the Environment, Te Papa Atawhai|accessdate=3 July 2017}} 3 : Pterostylis|Orchids of New Zealand|Plants described in 1853 |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。