Floating pennywort

Hydrocotyle ranunculoides

''Hydrocotyle ranunculoides'', known commonly as floating pennywort, or floating marshpennywort, is an aquatic plant in the family Apiaceae. It is native to North and South America and parts of Africa. In the United Kingdom it is an invasive alien species which is currently spreading in waterways.
Floating marshpennywort  Geotagged,Hydrocotyle ranunculoides,United States

Appearance

Water pennywort has stems that spread horizontally and can float on water. Leaves grow on petioles up to 35 cm long, and are round to kidney-shaped, with 3–7 lobes and crenate to entire margins. Flowers are small, pale greenish white to pale yellow, and come in umbels of 5–13. Fruits are small achenes that can float, helping the seeds to disperse.
Hydrocotyle ranunculoides This is a picture of Hydrocotyle ranunculoides at Broad Creek Park in Annapolis, Maryland. Floating pennywort,Geotagged,Hydrocotyle ranunculoides,Spring,United States

Distribution

It was one of five aquatic plants which were banned from sale in the UK from April 2014, and was the first prohibition of its kind there. Water pennywort is also a weed in Australia. On the other hand, it is a threatened species in parts of its native range in the United States.

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Taxonomy
KingdomPlantae
DivisionAngiosperms
ClassEudicots
OrderApiales
FamilyApiaceae
GenusHydrocotyle
SpeciesH. ranunculoides