protoperidinium

An illustration of the dinoflagellate (Dn) Protoperidinium depressum feeding on a chain of diatoms (Dt) using a pallium, a retractile organelle that spreads over the long spines of diatoms so that the contents can be digested.

Yes… dinoflagellates (microalgaes) can prey on diatoms (another microalgaes)..