Genetic and shell morphological variability of the invasive bivalve Corbicula fluminea (Müller, 1774) in two Portuguese estuaries
Genetic and shell morphological variability of the invasive bivalve Corbicula fluminea (Müller, 1774) in two Portuguese estuaries
复制标题
两个葡萄牙河口入侵双壳类河蚬 (Müller, 1774) 的遗传和贝壳形态变异
DOI：
10.1016/j.ecss.2007.04.011
复制
发表时间：
2007
期刊：
影响因子：
--
通讯作者：
L. Guilhermino
中科院分区：
文献类型：
--
作者：
R. Sousa;R. Freire;M. Rufino;J. Méndez;M. Gaspar;C. Antunes;L. Guilhermino
由于个体的贝壳形状、颜色和雕塑的高度多样性，因此对Corbcula属内不同物种的鉴定是复杂的。该种至少自1989年以来一直存在于葡萄牙西北部的米尼奥河河口。最近，同一属的个体在邻近的河口(利马河河口)定居。利马河口的个体与民荷河口的个体在贝壳的颜色和形状上有所不同。因此，通过常规的形态测量方法(壳长、壳宽和壳高)、几何形态计量学方法(利用壳内部的标志性分析)和遗传分析(基于线粒体细胞色素C氧化酶I亚单位的基因序列)对这两个种群进行了比较。遗传分析显示两个种群的mtCOI序列完全相同，表明这两个种群属于华支睾吸虫属种。然而，常规和几何形态计量学分析的结果表明，两个种群的个体在贝壳形状上存在显著差异。这些差异可能是由于(A)两个河口不同环境和/或生态条件下的表型可塑性，(B)种群的不同来源和/或到达两个河口前的不同路线，以及(C)在两个河口引入物种后发生的过程(例如差异选择)造成的种群间遗传差异。
The identification of different species inside the Corbicula genus is complicated due to the high variation of shell shape, colour and sculpture of the individuals. The species Corbicula fluminea has been present in the River Minho estuary (NW Portugal) at least since 1989. More recently, individuals of the same genus colonized an adjacent estuary (River Lima estuary). Although appearing also to be C. fluminea, the individuals of the Lima estuary differ from those of Minho estuary in the colour and shape of the shell. Therefore, the two populations were compared by conventional morphometric measures (shell length, width and height), geometric morphometric methods (landmarks analysis using the interior of the shell) and genetic analysis (based on the mitochondrial cytochrome c oxidase subunit I gene sequence). Genetic analysis showed an identical mtCOI sequence indicating that both populations belong to the species C. fluminea. However, results of conventional and geometric morphometric analysis showed significant differences in shell shape between individuals from the two populations. These differences may be due to (a) phenotypical plasticity in response to different environmental and/or ecological conditions existing in the two estuaries, (b) different origins of the populations and/or distinct routes until reaching the two estuaries and (c) inter-population genetic differences caused by processes occurring after the introduction of the species in the two estuaries (e.g. differential selection).