Euhydrophyte communities of Palaearctic streams moderately rich in nutrients, characterized in particular by Berula erecta (Sium erectum), Mentha aquatica f. submersa, Potamogeton perfoliatus, Potamogeton natans, Groenlandia densa, Ranunculus peltatus, Ranunculus penicillatus, Ranunculus trichophyllus, Ranunculus fluitans, Ranunculus aquatilis, Callitriche truncata, Callitriche stagnalis, Nymphaea alba, Myriophyllum spicatum.