This association includes stands of Myriophyllum alterniflorum, a submerged aquatic macrophyte occurring in oligo-mesotrophic to dystrophic streams with clear water. In contrast to the association Ranunculetum fluitantis, it is confined to lentic sections of streams with sandy to gravelly bottoms, at depths of 10–60(–100) cm. In the Czech Republic Myriophylletum alterniflori occurs only in the upper and middle Vltava river in southern Bohemia.