Nymphoides peltata

Nymphoides peltata, the fringed water-lily is perennial, rooted aquatic plant with floating leaves of the family Menyanthaceae. Synonyms include Menyanthes nymphoides L., Villarsia nymphoides, Limnanthemum peltatum S.G.Gmel., Nymphoides nymphoides (L.) Britton, and other vernacular names include yellow floating heart, floating heart, water fringe, and entire marshwort. It is native throughout most of Europe (excluding Ireland and Scandinavia) and temperate Asia, and locally in Algeria in northwest Africa. It has been spread by human cultivation outside its native range and is now naturalised in Ireland,, Denmark and Sweden, much of North America, and New Zealand. In many of its introduced regions, N. peltata is considered a noxious weed because it can form dense mats that shade out locally native aquatic plant species, thereby reducing biodiversity....read more on Wikipedia.