Abstract
On decaying wood or litter in forests, plasmodial slime molds (myxomycetes) represent a large
fraction of eukaryotic protists that feed on bacteria. In his seminal book Experimental Physiology of
Plants (1865), Julius Sachs referred to the multinucleate plasmodium of myxomycetes, which were
considered at that time as primitive plants (or fungi). Today it is well established that myxomycetes
are members of the Amoebozoa (Protista). In this study we compare the mobility of myxamoebae of
three European species, Lycogala epidendrum (order Liceales), Tubulifera arachnoidea, and Trichia
decipiens (order Trichiales). Using agar plates, on which three separate bacterial species were
cultivated as prey organisms (Methylobacterium mesophilicum, Escherichia coli, Agrobacterium
tumefaciens), we document large differences in cell motility between the myxomycetes investigated.
In addition, we show that the three species of myxamoebae can be distinguished based on their
average cell size. These data shed light on the mode of co-occurrence via differential substrate
utilization in these members of the Amoebozoa