Cryptic genetic diversity and host specificity of Bothriocephalus acheilognathi Yamaguti,1934(Eucestoda:Bothriocephalidea)

查看全文 作　　者：Bingwen [1,2]Xi;Wenxiang [3]Li;Guitang [3]Wang;Pin [3]Nie;Jun [1]Xie 机构地区：[1]Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization,Ministry of Agriculture,Freshwater Fisheries Research Center,Chinese Academy of Fishery Sciences,Wuxi 214081,China;[2]Hubei collaborative Innovation Center for Freshwater Aquaculture,Wuhan 430072,China;[3]State Key Laboratory of Freshwater Ecology and Biotechnology,and Institute of Hydrobiology,Chinese Academy of Sciences,Wuhan 430072,China 出　　处：《Zoological Systematics》索引2016年第41卷第2期,共9页 基　　金：supported by the National Natural Sciences Foundation of China(31302222);the Freshwater Fisheries Research Center,CAFS Grant(2013JBFM10);the earmarked fund for China Agriculture Research System(CARS-46) 摘　　要：In this report, genetic variation and phylogeny of B. acheilognathi were analyzed based on 96 samples collected from 20 fish host species in 29 different localities by using the r DNA internal transcribed spacer(ITS) sequences. The ITS1 and ITS2 sequences of B. acheilognathi varied among 561–639 bp and 559–648 bp, and ten simple sequence repeat loci(microsatellites) were detected in the ITS regions, which contributed to significant sequence length variation. Phylogenetic analyses revealed 4 genetic clades(A, B, C, D) in samples with significantly different fish host spectra and geographic distribution. Clade A possessed a wide host range and geographic distribution, including all the samples of B. acheilognathi determined in previous report. Clades B, C, and D only infected the small cyprinid fishes Opsariichthys bidens and Zacco platypus, and were limited to different locality. Interesting, Clades A and D were detected coexisting in same water body, and even in same fish host O. bidens in Danjiangkou Reservoir. The relatively higher genetic divergence and wide geographic distribution of B. acheilognathi parasitic in O. bidens indicated that O. bidens is likely to be the primary host. Sympatric occurrence of the two genetically distinct clades suggests the possibility of allopatric speciation and second encounter events. 关 键 词：宿主特异性 遗传多样性 系统发育分析 绦虫 内转录间隔区 简单重复序列 地理分布 序列分析