Wiktionary
hydrophily
n. A form of pollination whereby pollen is distributed by the flow of waters, particularly in rivers and streams.
Wikipedia
Hydrophily
Hydrophily is a fairly uncommon form of pollination whereby pollen is distributed by the flow of waters, particularly in rivers and streams. Hydrophilous species fall into two categories: those that distribute their pollen to the surface of water, and those that distribute it beneath the surface.