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.
Surface pollination is rare, and appears to be a transitional phase between wind pollination and true hydrophily. Surface hydrophily has been observed in several species of Potamogeton as well as some marine species.
- Cox, P.A. (1988). Hydrophilous pollination. Annual Review of Ecology and Systematics. 19(1): 261–279.