Waterpollinated

Waterpollinated, often described as hydrophily, is a mode of pollination in which pollen is transferred from the male structures to the female structures through water. This strategy is most common among submerged or partially submerged aquatic angiosperms and represents an adaptation to environments where pollinator activity is limited and wind dispersal is unreliable.

There are two main forms of waterpollination. Surficial hydrophily occurs when pollen is released into the water surface and is carried by currents to stigmas exposed at or near the surface. Submerged hydrophily takes place when both pollen and receptive stigmas are below the surface, with pollen either sinking to reach submerged stigmas or being guided by water movement toward them. Pollen and stigmas often exhibit specialized traits to facilitate water-mediated contact, such as buoyant or mucilaginous pollen or stigma surfaces adapted to capture suspended grains.

Distribution and examples of waterpollination are relatively limited among flowering plants. It is most prominent in several groups of aquatic plants, including some in the families Potamogetonaceae (pondweeds), Zosteraceae (seagrasses), Hydrocharitaceae (for example, Hydrilla), Vallisneriaceae (Vallisneria), and Najas. These plants may produce pollen that remains viable in aquatic conditions for a period sufficient to achieve successful fertilization, and flowering can be synchronized with water conditions to maximize transfer.

Ecological significance varies by species and habitat but generally enables sexual reproduction in aquatic ecosystems where pollinators are scarce. Limitations include reliance on water movement and timing, as well as the reduced efficiency of pollen travel over longer distances compared with wind or animal pollination.