| 词条 | Potamogeton natans |
| 释义 |
| image = PotamogetonNatans.jpg | status = LC | status_system = IUCN3.1 | status_ref = [1] | genus = Potamogeton | species = natans | authority = L. }} Potamogeton natans, commonly known as broad-leaved pondweed,[2] floating pondweed,[3] or floating-leaf pondweed, is an aquatic species in the genus Potamogeton native to quiet or slow-flowing freshwater habitats throughout the Holarctic Kingdom. DescriptionIt produces both floating and submersed leaves on the same plant. The floating leaves are ovate to oblong-ovate and almost always cordate at the base. They are dark green, leathery, opaque, with translucent longitudinal veins. They are 5 to 10 cm long, pointed at the tips, and rounded at the base. The stipules are 4 to 17 cm long. The submerged grass-like structures are called phyllodes, are actually modified leaf stalks. The stems are cylindrical, without many branches, and grow from 1 to 2 metres. The main difference between this species and other pondweeds is a discoloured flexible joint just below the top of the long leaf stalk. The flower spikes are dense, and cylindrical. They are 5 to 10 cm long, pointed at the tip and rounded at the base. It flowers from May to September. The fruits are 4 to 5 mm long and obovate.[4] References1. ^{{IUCN|id=164479 |title=Potamogeton natans |assessor=Gupta, A.K. |version=2013.1 |year=2013 |accessdate=24 June 2018}} 2. ^{{cite web |title=BSBI List 2007 |publisher=Botanical Society of Britain and Ireland |url=http://www.bsbi.org.uk/BSBIList2007.xls |format=xls |accessdate=2014-10-17 |deadurl=yes |archiveurl=https://www.webcitation.org/6VqJ46atN?url=http://www.bsbi.org.uk/BSBIList2007.xls |archivedate=2015-01-25 |df= }} 3. ^{{PLANTS|id=PONA4|taxon=Potamogeton natans|accessdate=13 October 2015}} 4. ^{{cite book |last=Rose |first=Francis|authorlink=Francis Rose |title=The Wild Flower Key |year=2006 |publisher=Frederick Warne & Co|isbn=978-0-7232-5175-0 |pages=490–491}} External links{{Commonscat}}{{Wikispecies}}
6 : Potamogeton|Freshwater plants|Flora of North America|Flora of Asia|Flora of Europe|Plants described in 1753 |
| 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。