Thecamoebidae

Description: Amoeba with a pellicle-like surface noticeable by a rather stiff appearance and, in this case, numerous wrinkles. Movement with a tractor-like rolling of the surface.  Size of locomotive form in this specimen 90x70 µm. Hyaloplasm as an antero-lateral crescent. Contractile vacuole located in posterior end of the cell. Nucleus spherical to ovoid, nucleolus of granular texture (see picture in lower right angle), sometimes divided in 2 or 3 fragments. Phase contrast ; nucleus in modified phase contrast. Amoeba was cultured in filtered water from original habitat and fed with Oscillatoria (Cyanobacteria), rests of which are seen in a food-vacuole in the centre.  It is one of the rugose species of the genus as described by Page and one of the typical representatives of Smirnov’s rugose morphotype.  A future zip-file may contain tables showing the peculiar phagocytosis of oscillatoria by Thecamoeba sphaeronucleolus as well as the fusion of two cells followed by encystment and cell division.  

Description: Amoeba with a pellicle-like surface noticeable by a rather stiff appearance and, in this case, numerous wrinkles. Movement with a tractor-like rolling of the surface.  Size of locomotive form in this specimen 90x70 µm. Hyaloplasm as an antero-lateral crescent. Contractile vacuole located in posterior end of the cell. Nucleus spherical to ovoid, nucleolus of granular texture, sometimes divided in 2 or 3 fragments. Phase contrast. Amoeba was cultured in filtered water from original habitat and fed with Oscillatoria (Cyanobacteria), rests of which are seen in a food-vacuole in the centre.  It is one of the rugose species of the genus as described by Page and one of the typical representatives of Smirnov’s rugose morphotype.  

Description: Amoeba with a pellicle-like surface noticeable by a rather stiff appearance and, in this case, numerous wrinkles. This image shows the nucleus at higher magnification (in the centre). It is spherical to ovoid, the nucleolus of granular texture, sometimes divided in 2 or 3 fragments. In the upper right corner a part of the contractile vacuole can be seen.  Modified Phase contrast.