GYMNODINIUM-NOLLERI ELLEGAARD ET MOESTRUP SP. INED. (DINOPHYCEAE) FROM DANISH WATERS, A NEW SPECIES PRODUCING GYMNODINIUM-CATENATUM-LIKE CYSTS - MOLECULAR AND TOXICOLOGICAL COMPARISONS WITH AUSTRALIAN AND SPANISH STRAINS OF GYMNODINIUM-CATENATUM

Gymnodinium nolleri Ellegaard et Moestrup sp. ined. (Dinophyceae) stra ins established from cysts collected at three marine locations in Denm ark were compared to Australian and Spanish strains of Gymnodinium cat enatum with respect to morphology, molecular characteristics, and cont ent of paralytic shellfish poisoning (PSP) toxins. The Spanish and Aus tralian strains were identical, but the Danish strains were smaller, f ormed only two-cell chains, and differed in rRNA sequence [large subun it (LSU) rRNA, D3 domain], and isozymes (malate dehydrogenase, esteras e, phosphoglucoisomerase, and superoxide dismutase). None of the Danis h strains tested contained detectable amounts of PSP toxins. In crossi ng experiments, Danish/Danish, Spanish/Spanish, and Spanish/Australian crosses produced cysts, but no resting cysts were found in Danish/Spa nish or Danish/Australian crosses. The name Gymnodinium nolleri Ellega ard et Moestrup will be validly published separately.