Potamogeton natans
Potamogeton natans | |
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Scientific classification | |
Kingdom: | Plantae |
(unranked): | Angiosperms |
(unranked): | Monocots |
Order: | Alismatales |
Family: | Potamogetonaceae |
Genus: | Potamogeton |
Species: | P. natans |
Binomial name | |
Potamogeton natans L. | |
Potamogeton natans (broad-leaved pondweed,[1] floating pondweed,[2] floating-leaf pondweed) is an aquatic species in the genus Potamogeton native to quiet or slow-flowing freshwater habitats throughout the Holarctic Kingdom.
Description
It 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.[3]
References
- ↑ "BSBI List 2007" (xls). Botanical Society of Britain and Ireland. Retrieved 2014-10-17.
- ↑ "Potamogeton natans". Natural Resources Conservation Service PLANTS Database. USDA. Retrieved 13 October 2015.
- ↑ Rose, Francis (2006). The Wild Flower Key. Frederick Warne & Co. pp. 490–491. ISBN 978-0-7232-5175-0.