Scholarlink

<p>A strain of benthic dinoflagellate <i>Prorocentrum formosum</i> was isolated from the Anding Lianjiao (Contiguous Reef) (also known as Addington Shoal), Zhongsha Islands. Morphological observation using light and scanning electron microscopy revealed vegetative cells measuring 24–27 µrn in length and 17–22 µm in width, which displayed an asymmetrical oval shape with smooth surfaces. The left and right valves contained two distinct types of radially arranged pores with differing diameters, characterized by sparsely distributed marginal pores and a seamless connection to the parallel horizontal intercalary band. The periflagellar area comprised 9 platelets arranged in a wide V-shape, containing both larger flagellar pores and smaller accessory pores. Phylogenetic analysis based on ITS and LSU rRNA gene sequences confirmed its classification within <i>Prorocentrum</i>, with strong bootstrap support (94% for ITS; 98% for LSU) and posterior probabilities (0.97 for ITS; 1.0 for LSU). Genetic distance analysis showed its closest relationship to <i>Prorocentrum elegans</i> (<i>P</i>=0.359 for ITS; <i>P</i>=0.118 for LSU). HPLC analysis detected chlorophyll <i>a</i>, chlorophyll <i>c</i><sub>2</sub>, peridinin, diadinoxanthin, and diatoxanthin. Although trace levels of okadaic acid (OA) were detected in the initial cultures, its production was no longer observed after prolonged cultivation of the strain. Toxicity tests demonstrated 72- and 96-h mortality rates of 18.75%±1.07% and 34.54%±2.71% in <i>Brachionus plicatilis</i> at 2 660 cells/mL, whereas <i>Artemia salina</i> exhibited no mortality after 96-h exposure. Hemolytic activity was not detected in algal extracts. This study provides the first molecular sequences of <i>P. formosum</i>.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Morphology and phylogeny of the rediscovered Prorocentrum formosum from the Zhongsha Islands, South China Sea

  • 期刊论文

  • 发表日期：

    2026年1月3日

查看全文
  • Jingyi Cen,
  • Hang Xie,
  • Yuan Huang,
  • Linjian Ou,
  • Songhui Lü,
  • Jianyan Wang

摘要

A strain of benthic dinoflagellate Prorocentrum formosum was isolated from the Anding Lianjiao (Contiguous Reef) (also known as Addington Shoal), Zhongsha Islands. Morphological observation using light and scanning electron microscopy revealed vegetative cells measuring 24–27 µrn in length and 17–22 µm in width, which displayed an asymmetrical oval shape with smooth surfaces. The left and right valves contained two distinct types of radially arranged pores with differing diameters, characterized by sparsely distributed marginal pores and a seamless connection to the parallel horizontal intercalary band. The periflagellar area comprised 9 platelets arranged in a wide V-shape, containing both larger flagellar pores and smaller accessory pores. Phylogenetic analysis based on ITS and LSU rRNA gene sequences confirmed its classification within Prorocentrum, with strong bootstrap support (94% for ITS; 98% for LSU) and posterior probabilities (0.97 for ITS; 1.0 for LSU). Genetic distance analysis showed its closest relationship to Prorocentrum elegans (P=0.359 for ITS; P=0.118 for LSU). HPLC analysis detected chlorophyll a, chlorophyll c2, peridinin, diadinoxanthin, and diatoxanthin. Although trace levels of okadaic acid (OA) were detected in the initial cultures, its production was no longer observed after prolonged cultivation of the strain. Toxicity tests demonstrated 72- and 96-h mortality rates of 18.75%±1.07% and 34.54%±2.71% in Brachionus plicatilis at 2 660 cells/mL, whereas Artemia salina exhibited no mortality after 96-h exposure. Hemolytic activity was not detected in algal extracts. This study provides the first molecular sequences of P. formosum.