The two previous videos show different species (Protoperidinium spp.) of dinflagellates pallium feeding on diatom chains. Similar to the seastars, the dinoflagellates evaginate a sort of “stomach ” to slowly digest the poor prey.
This snake-like thing that you see swimming all over the place is a Gyrodinium dominans that has engulfed a diatom chain.
Phoraminiphera can look peaceful unicellular guys. However, they are voracious predators. The one on the movie is trying to eat two copepods at the same time!
Plankton Ocean 