This is an annual or perennial plant found in ponds, lakes and rivers. It has white, 5-petalled flowers (15-30mm across) with a golden circle at the centre of the flower surrounding the matching stamens. It blooms in May and June on stalks which are longer than the leaf-stalks. It has two forms of leaves; those floating on the surface are rounded and lobed, those submerged are short and thread-like. This is a native plant belonging to the family Ranunculaceae.
I found this plant growing at the margins of the River Slaney at Scarawalsh, Co Wexford in 2008 and photographed it from the bank.
If you are satisfied you have correctly identified this plant, please submit your sighting to the National Biodiversity Data Centre