I have found some interessting PDF articles about the presence of Aldrovanda in the Dutch and Britisch Eemian.
The first reported macrofossils from Aldrovanda, Ceratophyllum and Salvinia are from Eefde, north of Zutphen.
Other locations of macrofossils and pollen of Aldrovanda, Brasenia and Salvinia where:
Zwartewater near Zwolle (pollen) and the Noordoostpolder (pollen and macrofossils)
Van der Vlerk and Florschutz (1950)
Both locations are in whats now the Ijssel vallei. The habitats where possibly in oxbowlakes because thats still an habitat of Aldrovanda vesiculosa in some parts of its present natural range. In the Eemian in that Ijjssel river was also hipothammus present.
Aldrovanda fossils have also been found in London (Trafalgar square) Again there was also Brasenia and also Trapa natans.
J.W. Franks (1959)
Aldrovanda and Brasenia are examples of a rich thermophilous aguatic flora of the warmer part of the Eemian.
These plants shared the Thames river vally with Hipothamus, Bos primigenius, Palaeoloxodon antiquas, Dama dama, Cerphus elephas, Rhinoceros and Panthera spelaea.
Well those where the good old days...