Hydrocotyle, also called floating pennywort, water pennywort, Indian pennywort, dollar weed, marsh penny, thick-leaved pennywort and white rot, is a genus of prostrate, perennial aquatic or semi-aquatic plants formerly classified in the family Apiaceae, now in the family Araliaceae.

Description

Water pennyworts, Hydrocotyles, are very common. They have long creeping stems that often form dense mats, often in and near ponds, lakes, rivers, and marshes, and some species in coastal areas by the sea.

Selected species

There are over 280 species recognised in the genus Hydrocotyle that grow in tropical and temperate regions worldwide. A few species have entered the world of cultivated ornamental aquatics. A list of selected species:

Distribution

Hydrocotyleae grow in wet and damp places in the tropics and the temperate zones.

Fossil record

One fossil fruit of a Hydrocotyle sp. has been extracted from borehole samples of the Middle Miocene fresh water deposits in Nowy Sacz Basin, West Carpathians, Poland.