Cryptophycean‐Like Double Membrane‐Bound Chloroplast in the Dinoflagellate, Dinophysis Ehrenb.: Evolutionary, Phylogenetic and Toxicological Implications

Abstract Dinoflagellates of the genus Dinophysis are responsible for diarrhetic shellfish poisoning. Phototrophic species have an orange primary fluorescence indicating the presence of phycobilins. The chloroplasts greatly resemble cryptophycean chloroplasts having pairs of thylakoids and electron‐dense material in the thylakoid lumen. They are bound by only two membranes, in contrast to the blue‐green chloroplasts of Amphidinium wigrense Woloszynsk, which are enveloped by three membranes (Wilcox and Wedemayer, 1985). Possible ways of evolution of the Dinophysis chloroplasts, phylogenetical questions and implications for the monitoring of toxic dinoflagellates are discussed.