53 LEMNA MINOR L.          1-6
   47 SPIRODELA POLYRRHIZA (L 1-6
   35 LEMNA MINOR L.          3-6
   28 SPIRODELA POLYRRHIZA (L 3-6
   26 AZOLLA FILICULOIDES LAM 1-6

   24 LEMNA GIBBA L.          1-6
   22 CERATOPHYLLUM DEMERSUM  1-6
   15 LEMNA TRISULCA L.       1-6
    8 CALLITRICHE OBTUSANGULA 1-6
    6 AZOLLA FILICULOIDES LAM 3-6

    4 LEMNA GIBBA L.          4-6
    2 POTAMOGETON TRICHOIDES  1-6
    2 BUTOMUS UMBELLATUS L.   1-5
    1 SALVINIA NATANS (L.) AL 1-6
    1 POTAMOGETON PUSILLUS L. 1-6

    1 HELODEA CANADENSIS RICH 1-6
    1 RANUNCULUS FLUITANS LAM 1-6