Paralytic shellfish poisoning (PSP) caused the deaths of four people in coastal area of Korea, mainly Jinhae-Masan Bay and adjacent areas, in April 1986 and in 1996. The PSP outbreaks were caused by the consumption of mussels, Mytilus edulis. The organism that caused PSP was identified, from morphological data only, as Alexandrium tamarense which is recently renamed as A. catenella, however recent studies have shown that the morphological diagnostic characteristics used to identify Alexandrium species have uncertainties and molecular tools and other criteria should be considered as well. The organism that caused past PSP outbreaks and incidents in Korea therefore need to be carefully reconsidered. The aim of this study was to re-evaluate the species really responsible for past outbreaks of PSP in Jinhae-Masan Bay, Korea. The temporal production and fluxes of the resting cysts of Alexandrium species were investigated for one year (from March 2011 to February 2012) using a sediment trap, and the morphology and phylogeny of vegetative cells germinated from the resting cysts were analysed. The production of Alexandrium species peaked in August and November, when temporal discrepancies were found in the water temperature (22.4 and 22.7 °C in August, 19.1 and 19.6 °C in November) and salinity (29.5 and 26.1 psu in August, 30.5 and 31.8 psu in November). The morphological data revealed that Alexandrium species germinated from resting cysts collected in August have a ventral pore on the 1′ plate, whereas the 1′ plate in Alexandrium species germinated from resting cysts collected in November lacks a ventral pore. Molecular phylogenetic data for the vegetative cells from the germination experiments allowed the August and November peaks to be assigned to Alexandrium catenella (Group I) and A. pacificum (Group IV), respectively. This indicates that the production of resting cysts of A. catenella can be enhanced by relatively high water temperature. This result is not consistent with those of previous studies that A. catenella responsible for PSP outbreaks was found at relatively low water temperature. In addition, large subunit ribosomal sequences data revealed that A. pacificum isolates from Korea were closely related to those from Australia, Japan and New Zealand where the PSP toxicity of shellfish and blooms occurred in the 1990s, indicating that the introduction of toxic dinoflagellates were related to ballast water from bulk-cargo shipping. Based on these results, we concluded that past PSP outbreaks in Jinhae-Masan Bay of Korea could have been caused by A. pacificum rather than by A. catenella.

麻痹性贝毒（PSP）造成四人死亡的朝鲜的沿海地区，主要是镇海，马山湾和邻近地区，在1986年4月和1996年的PSP爆发是由贻贝，消耗造成的贻贝。仅从形态学数据中鉴定出引起PSP的生物为塔玛亚历山大藻，最近将其重命名为A. catenella，但是最近的研究表明，形态学诊断特征可用于鉴定亚历山大藻物种具有不确定性和分子工具，还应考虑其他标准。因此，需要仔细考虑在韩国造成过去PSP爆发和事件的生物。这项研究的目的是重新评估真正导致过去在韩国金海-马桑湾爆发PSP的物种。使用沉积物捕集器调查了亚历山大藻物种静止囊肿的暂时产量和通量，为期一年（2011年3月至2012年2月），并分析了静止囊肿中萌发的营养细胞的形态和系统发育。亚历山大的生产物种在8月和11月达到顶峰，当时发现水温（8月为22.4和22.7°C，11月为19.1和19.6°C）和盐度（8月为29.5和26.1 psu，11月为30.5和31.8 psu）存在时间差异。 。形态学数据显示，从8月收集的静息囊肿发芽的亚历山大藻物种在1'平板上有一个腹孔，而从11月收集的静息囊肿萌发的亚历山大藻物种的1'平板上没有腹孔。来自萌发实验的营养细胞的分子系统发育数据允许将八月和十一月的峰分配给亚历山大连叶藻（第一类）和太平洋曲霉（第四组）。这表明，相对较高的水温可以提高链状土壤杆菌静息囊肿的产生。该结果与先前的研究不一致，后者是在相对较低的水温下发现了引起PSP爆发的链孢曲霉。此外，大的亚基核糖体序列数据表明，A。pacificum来自韩国的分离物与澳大利亚，日本和新西兰的分离物密切相关，在澳大利亚，日本和新西兰，贝类和水华的PSP毒性发生于1990年代，这表明有毒的鞭毛藻的引入与散装货物运输中的压舱水有关。根据这些结果，我们得出结论，过去在韩国金海-马桑湾爆发的PSP可能是由太平洋A.而不是由A. catenella引起的。