Tang Weixing, Chen Yifeng
Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
Zoolog Sci. 2012 May;29(5):311-8. doi: 10.2108/zsj.29.311.
Hybridization with introduced fish species is an important threat to native fish species. Here we investigated hybridization between native barbless carp (Cyprinus pellegrini) and introduced common carp (C. carpio) in Xingyun Lake in the Yunnan-Guizhou plateau of China. A total of 203 individuals of Cyprinus from Xingyun Lake were studied by combination of morphological and genetic analyses. Most individuals were strictly intermediate between the two parental species in morphology, strongly suggesting that extensive hybridization has occurred. Bayesian model-based clustering of the genetic data suggests that there are two distinct genetic groups corresponding to barbless and common carp respectively. Many individuals in the two genetic groups showed intermediate morphology, suggesting that both groups actually contain massively introgressed genes. Only two individuals were identified as barbless carp both morphologically and genetically, hinting that this native species is at risk of genetic extinction in Xingyun Lake.
与外来鱼类物种杂交是对本地鱼类物种的一个重要威胁。在此，我们调查了中国云贵高原星云湖中的本地无鳞鲤（Cyprinus pellegrini）与外来鲤鱼（C. carpio）之间的杂交情况。通过形态学和遗传学分析相结合的方法，对星云湖中的203个鲤属个体进行了研究。大多数个体在形态上严格处于两个亲本物种之间，强烈表明已经发生了广泛的杂交。基于贝叶斯模型的遗传数据聚类分析表明，存在两个不同的遗传群体，分别对应无鳞鲤和鲤鱼。两个遗传群体中的许多个体表现出中间形态，表明这两个群体实际上都含有大量渗入的基因。只有两个个体在形态和遗传上都被鉴定为无鳞鲤，这暗示该本地物种在星云湖面临基因灭绝的风险。
