中国西沙群岛底栖甲藻热带库里亚藻(Coolia tropicalis)的形态学、系统发育及毒性研究

库里亚藻(Coolia)是一类广泛分布且具有生物毒性的海洋底栖甲藻。本研究对近年来在中国南海西沙群岛海域采集分离的4株库里亚藻, 通过光镜及电镜下的形态学观察, 并结合基于核糖体大亚基(large subunit, LSU)rDNA(D1-D3)和内部转录间隔区(internal transcribed spacer, ITS)的序列进行系统发育分析, 鉴定该4个株系为热带库里亚藻(Coolia tropicalis)。在卤虫(Artemia salina)生物毒性试验中, 热带库里亚藻不同株系毒素提取液对卤虫幼虫表现出了毒性差异, XS554株系的48h半致死浓度(LC50)为1.42mg·mL ^-1(约相当于1.1×10 ⁵cells·mL ^-1), 5XS15株系的LC50为1.92mg·mL ^-1(约相当于1×10 ⁵cells·mL ^-1)。

Morphology,phylogeny and toxicity of Coolia tropicalis (Dinophyceae) from the Xisha Islands,China

Coolia is a widespread and toxic genus of benthic marine dinoflagellate. In this study, four strains of Coolia species were examined as Coolia tropicalis, which were collected in the Xisha Islands of the South China Sea in recent years. Morphology was determined using light microscopy and scanning electron microscopy. Phylogenetic analyses were constructed based on the sequences of the large subunit rDNA and the internal transcribed spacer region. The bioassay toxicity test of brine shrimp (Artemia salina) demonstrated that the algal lysates extracted from different strains of C. tropicalis exhibited different toxic effects. At 48 h, the LC50 of XS554 strain was 1.42 mg·mL ^-1 (approximately 1.1×10 ⁵ cells·mL ^-1) and 5XS15 strain was 1.92 mg·mL ^-1 (approximately 1×10 ⁵ cells·mL ^-1).