中文摘要：

为查明我国金鱼三代虫的种类,研究采用形态学与分子生物学相结合的方法,对我国6个金鱼主要养殖区的三代虫进行了调查。通过形态测量分析,发现了4种三代虫,分别为:小林三代虫(Gyrodactylus kobayashii)、G.gurleyi、G.longoacuminatus和三代虫未定种(Gyrodactylus sp.)。而通过核糖体rDNA ITS序列比对分析,发现有2种三代虫分别与小林三代虫和G.longoacuminatus相似性在99.1%以上,有1种与G.gurleyi的相似性在98.2%以上,另外,还有1种三代虫与现有序列的相似性都较低,虽然它与小林三代虫的相似性最高,也仅为91.0%,暂为未定种。系统发育分析也显示,金鱼寄生的3种三代虫分别与小林三代虫、G.gurleyi和G.longoacuminatus聚集在一起,另外1种单独聚在一起,这4种三代虫均隶属于G.(Limnonephrotus)亚属,与G.(Gyrodactylus)亚属的秀丽三代虫(G.elegans)的亲缘关系很远。通过对三代虫样品的抽样调查发现,小林三代虫存在于所有采样点,在广州、武汉、郑州3个采样点为优势种,所占的比率都在60%以上;G.gurleyi在海口、南京和上海为优势种,所占的比率都在50%以上;G.longoacuminatus和三代虫未定种所占比率均较小。由此可见,小林三代虫和G.gurleyi是我国金鱼常见的三代虫,G.gurleyi和G.longoacuminatus是中国三代虫新记录种。

英文摘要：

In order to determine the Gyrodactylus species in China, we applied morphological and molecular approaches to identify specimens of Gyrodactylus collected from 6 principal goldfish farming areas. Four Gyrodactylus species, including G. kobayashii, G. gurleyi, G. longoacuminatus and G. sp., were identified with morphological measurements. According to rDNA ITS sequence alignment, 2 species of Gyrodactylus were identical to G. kobayashii and G. lon-goacuminatus with a similarity of higher than 99.1%. One species of Gyrodactylus was identical to G. gurleyi with the similarity higher than 98.2%. The other Gyrodactylus species had low similarity to all the currently available sequences, with the relatively high similarity of only 91.0% to G. kobayashii. The results of Phylogenetic analysis indicated that these three Gyrodactylus species were clustered with G. kobayashii, G. gurleyi and G. longoacuminatus, respectively. The fourth Gyrodactylus species clustered in a separate clad. All the 4 Gyrodactylus species in goldfish belonged to G. (Limnonephrotus), and they were distant from G. elegans that belonged to G. (Gyrodactylus). G. kobayashii was found in all sampling areas and was dominant in Guangzhou, Wuhan and Zhengzhou with a proportion of more than 60%. G. gurleyi was found in 5 areas except for Zhengzhou, and dominated in Haikou, Nanjing and Shanghai with the percentage of higher than 50%. G. longoacuminatus and G. sp. formed a small proportion. The results suggested that G. kobayashii and G. gurleyi were the most common Gyrodactylus species in goldfish, and G. gurleyi and G. longoacuminatus were the newly reported in China.