Hydrocotyle ranunculoides

Hydrocotyle ranunculoides
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Apiales
Family:	Apiaceae
Genus:	Hydrocotyle
Species:	H. ranunculoides
Binomial name
Hydrocotyle ranunculoides L. f.

Floating pennywort infestation in the River Soar, Leicester

Hydrocotyle ranunculoides, known commonly as water pennywort or floating pennywort, 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.^[1][2][3] It is one of five aquatic plants which are to be banned from sale in the UK from April 2014. This is the first prohibition of its kind in the country.^[4] 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.^[5]

Water pennywort has stems that spread horizontally and can float on water.^[6] Leaves grow on petioles up to 35 cm long, and are round to kidney-shaped, with 3–7 lobes and crenate to entire margins.^[7] Flowers are small, pale greenish white to pale yellow, and come in umbels of 5–13.^[6] Fruits are small achenes that can float, helping the seeds to disperse.^[6]

References