Does The Fish-Killing DinoflagellateGymnodiniumCF.NagasakienseProduce Cytotoxins?

The naked dinoflagellateGymnodinium cf. nagasakienseis responsible for red tides frequently associated with mortality of marine organisms in North European waters during summer (see reviews by Tangen, 1977 and Partensky & Sournia, 1986). This species is currently referred to asGyrodinium aureolumHulburt in the literature, since its first occurrence in Norwegian waters in 1966 (Braarud & Heimdal, 1970). However, it was recently found to be morphologically closer to the Japanese bloom-forming speciesGymnodinium nagasakienseTakayama & Adachi than to the originalGyrodinium aureolum(Partenskyet al., 1988).