Pollination with the help of water is called hydrophily. Plants, which occur below the water level are called sub-merged plants. When pollination occurs in these plants, it is called hypohydrophily, $e.g.,$ $Zostera,\ Najas,$ etc.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.