Thecamoeba sp.

Diagnosis: Surface smooth in locomotion, with some longitudinal dorsal folds; outline in locomotion oblong or oval; hyaloplasm usually an antero-lateral crescent; nucleus with a single central nucleolus of homogeneous texture; nucleolus irregular, oblong; a single contractile vacuole.

Dimensions: Length ca. 35 µm, length: breadth ratio 1.7; nucleus 6-7 µm.

Ecology: fresh water.