Close up of the leaves and 3-petalled flower.
Hydrocharis morsus-ranae NS5866 27July2018 PW
Hydrocharis morsus-ranae NS5866 27July2018 PW
The flat leaves and the single flower are the Frogbit, centre right is also Berula erecta Lesser Water-parsnip. This being Lanarkshire, someone has also discarded a plastic bottle to provide scale. They are much smaller than water-lilies.
Hydrocharis morsus-ranae NS5866 27July2018 PW