Dinokaryota
Dinokaryota is the main class of dinoflagellates. They include all species where the nucleus remains a dinokaryon throughout the entire cell cycle, which is typically dominated by the haploid stage. All the "typical" dinoflagellates, such as Peridinium and Gymnodinium, belong here. Others are more unusual, including some that are colonial, amoeboid, or parasitic. Symbiodinium contains the symbiotic zooxanthellae.
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