单殖吸虫是动物寄生虫的一个重要类群，主要寄生于鱼类的鳃和体表，具有丰富的物种多样性和高度的宿主特异性，亦是养殖鱼类的重要病原生物之一。我国南海三沙海域岛礁众多、鱼类资源丰富，但三沙鱼类单殖吸虫研究记录空缺，其种类组成与感染状况等基础性资料亟待补充。本项目拟通过标本的采集制备及显微观察测量对单殖吸虫进行分类学研究，以查清我国三沙海域鱼类寄生单殖吸虫的种类、宿主分布和区系特点；同时测定所获单殖吸虫的核基因ITS、18S与28S rDNA及线粒体基因COI的序列，为形态存疑种的区分提供分子依据、为我国单殖吸虫分子条形码数据库的建立积累资料；并基于分子数据构建系统树、探讨部分单殖吸虫的亲缘关系及其与宿主鱼的共进化关系。研究结果将填补我国南海三沙海域鱼类寄生单殖吸虫区系分类研究之空缺，推动我国鱼类寄生单殖吸虫物种多样性和系统发育研究，并为三沙鱼类资源的保护及相关病害的防控提供科学依据。

Monogeneans mainly parasiting on the gills or body surface of fishes, and with rich species diversity and high host specificity. Members of them are important pathogens for aquaculture. Sansha Islands in the South China Sea is a typical coral reef ecosystem and contains high fish species richness. This project will focus on the monogeneans parasitized on the marine fishes from Sansha Islands of the South China Sea. The identification, classification and molecular phylogenetic analysis of the collected specimens of monogeneans from Sansha Islands will be done for understanding the species diversity and phylogenetic relationships of those worms. The results will fill up the vacancy of fauna and taxonomic studies on monogeneans from the Sansha Islands, and will promote the development of species diversity and phylogeny of monogeneans from China, and provide valuable information for the protect coral reef fish’s resource and control of fish diseases caused by these kinds of parasites.