Peruvian Primrose is an perennial exotic plant to Sri Lanka native to american continent but now naturalized many countries in the world including India and Australia. It is commonly found in fens, marshes and along the edges of paddy field widely in Wet Zone. The plant is a one of exotic species of Ludwigia genus which is called in Sinhalese Diya Milla, and Boru Diya Milla. It is one of the most noxious invasive weeds on adjacent area of water bodies.
Other exotic species of the genus Luwigia : Ludwigia Longifolia
Native species of Ludwigia genus : Ludwigia adscendens, Ludwigia perennis, Ludwigia hyssopifolia, Ludwigia prostrata and Ludwigia octovalvis.