1999年 5月在广东省惠阳大亚湾发生一起Peridinium quinquecorne赤潮。利用光镜和电镜对赤潮生物进行形态学观察。赤潮期间 ,赤潮生物最高密度可达 11.8× 10 6L-1,随着气温骤降 ,赤潮消退。P .quin quecorne是一喜生活在富营养化的浅湾内兼具附着、浮游习性的种类 ,针对赤潮发生区域的营养盐与该种赤潮发生的关系作了探讨。 In May 1999, a Peridinium quinquecorne red tide occurred in Daya Bay, Huiyang, Guangdong Province. The morphology of red tide organisms was observed by light and electron microscopy. Red tide period, the highest density of red tide organisms up to 11.8 × 10 6L-1, with the temperature plummeted, red tide subsided. Pquinquin quecorne is a kind of living in the eutrophic shallow bass both the attachment, planktonic habits of species, the occurrence of red tide nutrients and the relationship between the occurrence of the red tide were discussed.