Riella
... that Riella is the only liverwort to grow as a submerged aquatic?
... that <i id="mwEP0"><b id="mwEP4"><a href="./Riella" id="mwEP8" rel="mw:WikiLink" title="Riella">Riella</a></b></i> is the only <a href="./Marchantiophyta" id="mwEQA" rel="mw:WikiLink" title="Marchantiophyta">liverwort</a> to grow as a <a href="./Aquatic_plant" id="mwEQE" rel="mw:WikiLink" title="Aquatic plant">submerged aquatic</a>?