It is very unusual for an aquatic plant to be limited to just one location, for their seeds are usually scattered far and wide via waterborne routes or by migratory birds.
由於水生植物多為「水媒花」，傳播力無遠弗屆，加上湖泊常有候鳥停棲，南來北往的雁鴨到處留「種」，因此水生植物少有侷限於一地而獨自發展出特色的特有種。