Comprehensive DescriptionRead full entry
Description of ThecamoebaAmoebae within this genus are ovoid or oblong in shape and may have well-developed longitudinal surface folds or wrinkle when they move. The cells are usually between 30 and 350 µm long and never branched. Anterior edge semi-circular with an extensive hyaloplasm that can occupy more than half the cell. Posterior edge often slightly convex, sometimes with a knob uroid. This surface structure is undoubtedly related to the thick, dense gycocalyx that typifies this genus. Amoebae often with a prominent anterior hyaloplasm that may extend along the sides towards the posterior of the cell. The form of the nucleus is an important diagnostic feature. The nucleolus can be central, with large or small parietal nucleolar lobes or be a coarsely granular central mass. Some species have rounded posterior regions while others have a tendency to form a knobbly or shrivelled uroid. At least 12 species described from freshwater, however, no cyst stages have been reported. Common. Widespread distribution in Europe, North America and Australia. Type species: T. quadripartita Fromentel 1874.