Abstract
The fossil dinoflagellate cyst genus Ceratiopsis Vozzhennikova 1963 is a junior homonym of the fungal genus Ceratiopsis De Wildeman 1896. Accordingly, those species formerly included in Ceratiopsis Vozzhennikova are transferred to the genus Cerodinium Vozzhennikova 1963. This has necessitated the emendation of Cerodinium.