Free-floating duckweed vegetation of still and relatively nutrient-rich freshwater bodies of the Holarctic
Vascular plants: Azolla cristata, Azolla filiculoides, Hydrocharis morsus-ranae, Landoltia punctata, Lemna aequinoctialis, Lemna gibba, Lemna minor, Lemna minuta, Lemna trisulca, Lemna turionifera, Salvinia molesta, Salvinia natans, Spirodela polyrhiza, Stratiotes aloides, Wolffia arrhiza