Sorry to revive a very old thread, but I am not convinced these are Euglenoids. Please do note that I do not pretend to know much about algae or biology for that matter, but here is what bugs me about this ID:
1. I see no red eye spot, even in the palmelloid state I have seen red eyespots when I performed some research.
2. The palmelloid state is supposedly for when conditions are suboptimal, however I only ever see this algae in my tank in this state, never found a single motile euglenoid, and this is the state the algae reproduces profusely in.
3. I see no starch bundles inside these cells.
Is it not possible these are some kind of algal spore?
Here is another photo under 100x objective:
