Echinidinium zonneveldiae sp. nov., a dinoflagellate cyst from the Late Pleistocene of the Baltic Sea, northern Europe

Abstract. The dinoflagellate cyst species Echinidinium zonneveldiae sp. nov. is described from last interglacial (Eemian Stage; Upper Pleistocene) deposits of the southern Baltic Sea, where it contributes to the characterization of a diverse interglacial dinoflagellate flora represented by more than 50 species. Echinidinium zonneveldiae is a probable heterotrophic species and does not occur in the region today. The nomenclatural status of the genus Echinidinium Zonneveld, 1997 ex Head et al., 2001a is clarified, and it is noted that two of the seven species assigned to Echinidinium are not validly described.