I find Euglena hemichromata frequently and regularly in the Simmelried. The specimens are usually found in the uppermost mud layer. I have not yet been able to find Euglena hemichromata in my other locations.

Euglena hemichromata is very easy to recognize and identify due to the two-coloured cells. The anterior half is usually colorless or slightly brownish and completely filled with paramylon grains, while the posterior half is green due to chloroplasts of the cell which are located there (s. fig. 1 a-c). Because the chloroplasts are densely packed in the posterior half, their shape is difficult to recognize. In this species, the shape can vary between short ribbon-shaped, disc-shaped or even irregularly shaped plates. In my population they were mostly short ribbons (s. fig. 3 a).

In my population of Euglena hemichromata I could recognize numerous spindle-shaped mucocysts under the pellicle (s. figs. 2 and 3 a), which are not mentioned by Skuja (1948). I do not know whether these are only formed temporarily or are permanently present.

In young cells of Euglena hemichromata, the chloroplasts are still distributed throughout the cell, which makes identification very difficult. At this stage, Euglena hemichromata is very similar to Euglena viridis. Only with the increasing formation of paramylon, the chloroplasts are displaced to the posterior end of the cell, resulting in the typical two-colored appearance.