Abstract:
Taenioides sp. is a small temperate fish originally known to inhabit muddy bottoms of brackish waters in coastal areas of China. However, it began to invade multiple inland freshwaters and caused severe damage to Chinese aquatic ecosystems in recent years. To investigate the sources and invasive history of this species, we examined the population structure of 141 individuals collected from seven locations based on partial mitochondrial D-loop regions. The results revealed that the genetic diversity gradually decreased from south to north, with the Yangtze River Estuary and Taihu Lake populations possessing the highest haplotype diversity (Hd), average number of differences (k), and nucleotide diversity (π) values, suggesting that they may be the sources of Taenioides sp. invasions. Isolation-by-distance analysis revealed a non-significant correlation (p = 0.166) between genetic and geographic distances among seven populations, indicating that dispersal mediated through the regional hydraulic projects may have played an essential role in Taenioides sp. invasions. The population genetic structure analysis revealed two diverged clades among seven populations, with clade 2 only detected in source populations, suggesting a possible difference in the invasion ability of the two clades. Our results provide insights into how native estuary fish become invasive through hydraulic projects and may provide critical information for the future control of this invasive species.
摘要:
Taenioidessp.是一种小型温带鱼类,最初已知栖息在中国沿海地区微咸水域的泥泞底部。然而,近年来,它开始入侵多个内陆淡水,并对中国水生生态系统造成严重破坏。为了调查该物种的来源和入侵史,我们基于部分线粒体D环区,对从7个地点收集的141例个体的种群结构进行了研究.结果表明,遗传多样性从南到北逐渐降低,长江口和太湖种群具有最高的单倍型多样性(Hd),平均差异数(k),和核苷酸多样性(π)值,这表明它们可能是Taenioidessp的来源。入侵。隔离距离分析显示,七个种群之间的遗传距离和地理距离之间存在非显着相关性(p=0.166),表明通过区域水利工程介导的分散可能在Taenioidessp。入侵。种群遗传结构分析揭示了七个种群中有两个分化的进化枝,进化枝2只在源种群中检测到,这表明两个进化枝的入侵能力可能存在差异。我们的结果提供了有关本地河口鱼类如何通过水利工程入侵的见解,并可能为将来控制这种入侵物种提供关键信息。