Genus: Usually limax-like, commonly with villous-bulb uroid; locomotion by steady flow with occasional slight antero-lateral bulging; floating form with long, blunt, mostly granular pseudopodia; normally uninucleate (Page, 1976). Pseudopods do not meld at bases during locomotion; pseudopods not ridged; nucleus spherical (Illustrated Guide, 1985). Species: 100-150 μm long; relatively slender (?), L/B 2-5; nucleus 13-17 μm (Page, 1976). Bag-like in locomotion with trailing bulge (uroid and filaments), broader at anterior than at posterior (How to know the protozoa, 1979). monopodal 150-180 μm long; uroid a semipermanent disc wifh fine filaments; nucleus spherical 13-17 μm, no endosome; contractile vacuole 15-20 μm diam. (Illustrated Guide, 1985).