Trichamoeba sinuosa Siemensma & Page, 1986
Diagnosis: fast locomotion in typical zigzag shape; uroid bulbous, smooth or with short villi; usually with many bipiramidal crystals; nucleus with small peripherally arranged nucleoli.
Dimensions: length 125-325 µm, mean 200 µm; L:B > 4, usually >5; nucleus ca. 14-27 µm, mean 20 µm.
Ecology: on water plants and on the bottom of different types of water; the type material was collected from a polluted canal in Kortenhoef (The Netherlands).
Remarks: the monopodial form is a typical zigzag movement, hence the name ‘sinuosa’. Cysts have two small nuclei; up to 3 ectolayers.
T. sinuosa resembles a Saccamoeba, but can be distinguished from the latter by its characteristic granular nucleus.
This amoeba is not rare, and easy to culture. In cultures specimens with two nuclei have been observed.