Bog bean is an aquatic perennial found across the Northern Hemisphere, including most of the UK. Its a monotypic genus (only one species), but a closely related genus, Nymphoides peltata, the fringed water-lily, is in the same family (Menyanthaceae), has similar 'fringed' or 'feathery' flowers. According to some research this a device to deter ants!
As with all pond marginals, Menyanthes provides structure to the aquatic environment, shelter for everything from invertebrates to amphibians and grass snakes. Add to that the sparkling floral display which attracts all manner of pollinators, especially bees, flies and butterflies, and the leaves that are one of the food plants of caterpillars of the dramatice elephant hawk-moth, and you have a perfect plant for all.