Flowers perfect (bisexual), or imperfect (unisexual), not showy.
Stems stiff and erect emerging from the water.
Closely related to the Haloragaceae (Water-milfoil Family). They used to be one.
Apparently only three very closely related species worldwide. Some taxonomists consider them all subspecies of H.vugaris.
Central Yukon:(CYSIP study area)