Dinoflagellate cysts in recent marine sediments from the east coast of Russia

Forty-two different dinoflagellate cyst types were found in recent sediment samples collected between July 1999–September 2002 from 44 stations along the eastern coast of Russia. This represents the first survey of recent dinoflagellate cysts in Russian marine waters. Forty cysts were identified to the species level, representing 17 genera. The most common cysts were those of ellipsoidal Alexandrium spp., Protoceratium reticulatum, Gonyaulax spp. , Polykrikos kofoidii, P. schwartzii , Protoperidinium americanum, P. minutum , P. conicoides , P. subinerme , P. conicum and Scrippsiella trochoidea . Fifteen of the dinoflagellate species have not previously been recorded as motile cells in Russian marine waters: Alexandrium cf. minutum , Cochlodinium cf. polykrikoides , Diplopsalis cf. lebourae , Fragilidium mexicanum, Gonyaulax elongata, G. membranaceae, Gymnodinium cf. catenatum , Pentapharsodinium dalei , P. tyrrhenicum , Protoperidinium americanum , P . cf. avellanum , Scrippsiella cf. lachrymosa , S . cf. precaria , S . cf. rotunda and Warnowia cf. rosea . Cysts of the potentially toxic species Alexandrium cf. minutum , A . tamarense and Gymnodinium cf. catenatum were also found in this survey. Ellipsoidal Alexandrium tamarense type cysts were widely distributed and dominated many localities in the study area. These data suggest that additional cyst surveys should be conducted in areas of the eastern Russian coastline not yet investigated, and that the potential for paralytic shellfish poisoning toxicity as a result of blooms of toxic species may be more widespread than previously documented.