Dinocysts or dinoflagellate cysts are typically 15 to 100 µm in diameter and produced by around 15-20% of living dinoflagellates as a dormant, zygotic stage of their lifecycle, which can accumulate in the sediments as microfossils. Organic-walled dinocysts are often resistant and made out of dinosporin. There are also calcareous dinoflagellate cysts and siliceous dinoflagellate cysts. Many books provide overviews on dinocysts.

Dinocysts or dinoflagellate cysts are typically 15 to 100 µm in diameter and produced by around 15-20% of living dinoflagellates as a dormant, zygotic stage of their lifecycle, which can accumulate in the sediments as microfossils. Organic-walled dinocysts are often resistant and made out of dinosporin. There are also calcareous dinoflagellate cysts and siliceous dinoflagellate cysts. Many books provide overviews on dinocysts.