蛎甲藻属是一类可形成有害藻华的底栖有毒甲藻，能够产生目前已知毒性最强的非蛋白类藻毒素-海葵毒素，且其分布范围具有不断扩大的趋势，近年来引起了国际有害藻华研究领域的广泛关注，成为该领域研究热点之一。我国对于蛎甲藻的研究极为稀少，本项目拟从形态分类学、分子系统学和毒性研究为切入点，全面揭示我国南海的蛎甲藻属种类多样性、分布特征、分子特性、毒性及产毒调控的环境因素等。为实现上述目标，本研究将通过对我国南海近岸及代表性岛屿的底栖甲藻样品进行广泛采集、分离、鉴定及系统发育研究，确定其生物多样性及其分类学地位；通过实验室批量培养及其不同培养条件的胁迫，研究蛎甲藻的毒性及其环境调控机制。本研究结果将为蛎甲藻属种类在全球分布的态势分析填补我国海区的空白，并对全面了解我国海洋底栖有毒甲藻的生物多样性提供依据，同时为底栖甲藻藻华的防灾减灾提供科学依据。

The Ostreopsis is the toxic benthic dinoflagellate genus which produce palytoxin(PLTX) and its analogs, one of the most potent toxic compounds. The species of this genus are widely distributed in tropical and subtropical seas. They are extending to the temperate waters. Harmful events associated with Ostreopsis, have been reported more frequently over the last decade including in areas where those benthic genera were hardly known. Except that of ciguatera fish poisoning (CFP) produced by Gambierdiscus, one of the most popular algal toxins in benthic ecosystem, the palytoxin produced by Ostreopsis is another important toxins in benthic ecosystem and are responsible for one of the most common algal toxin-related illnesses globally and often with significant long-term ecosystem negative effects. So far Ostreopsis have not been extensively investigated worldwide. The biodiversity of this genus have never been studied in the nearshores in the south China benthic ecosystems. The phylogeny, toxicity, and degree to which various environmental factors regulating the distribution and toxicity of individual Ostreopsis populations are largely unknown and would be a major focus on the study. The South China Sea and islands within the areas is a typical tropical and subtropical ecosystems with rich substrates for benthic dinoflagelles growth. We propose to study the biodiversity, phylogeny and toxicity of benthic Ostreopsis in the area. The objectives for the study are to answer the following scientific questions: The biodiversity and the distribution pattern of the species in the area, the phylogeny of Ostreopsis species and their relationship with strains from the nearby waters, the toxicity of the species and the environmental parameters that affect the local distribution and the toxin production.