Marine Biological Resources Institute, Sahmyook University, Seoul, South Korea.
Department of Animal Biotechnology and Resource, College of Science and Technology, Sahmyook University, Seoul, South Korea.
PeerJ. 2022 Sep 2;10:e14002. doi: 10.7717/peerj.14002. eCollection 2022.
The ivory barnacle is a marine crustacean, which presents near-cosmopolitan distribution due to extensive introduction and exhibits a wide spectrum of phenotypic variation. To elucidate geographical differentiation among populations through invasion, we investigated variation in genetic structure, shell morphology, and recruitment pattern for , from the southern Korean Peninsula where it has been established since the late 1980s. We selected samples from four populations in corresponding ecologically-relevant regions representing all surrounding South Korean waters. From these we amplified the mitochondrial genetic marker cytochrome oxidase subunit I (COI) from 57 individuals and performed a populational genetic analyses with 11 additional GenBank sequences to evaluate population structure. To examine morphological variation, we applied two-dimensional landmark-based geometric morphometrics to the scutum and tergum for 148 and 151 individuals, respectively. Furthermore, we estimated the density of year-old individuals in the field to compare recruitment responses among localities. We detected 33 haplotypes among the four locations belonging to three distinct clades based on moderate intraspecific pairwise genetic distance (≥3.5%). The haplotypes in these clades were not locality-specific in their distribution. In contrast, we did detect interpopulation variation in opercular shape and morphospace structure, and one population could be separated from the rest based on its distinct tergum morphotype alone. This morphologically distinct population was also differentiated by displaying the lowest mean recruitment density. Our results indicate that although there is no relationship between molecular variation in the COI gene and geographic regions in South Korea, association with locality for operculum morphology, and recruitment response suggest ecological adaptation by this barnacle in a new habitat.
象牙藤壶是一种海洋甲壳类动物，由于广泛的引入和表现出广泛的表型变异，呈现出近乎世界性的分布。为了阐明通过入侵导致的种群地理分化，我们调查了遗传结构、壳形态和繁殖模式的变化，研究对象是自 20 世纪 80 年代末以来在韩国南部建立的种群。我们从四个具有代表性的生态相关区域的种群中选择了样本，代表了所有韩国周边海域。从这些样本中，我们从 57 个个体中扩增了线粒体遗传标记细胞色素氧化酶亚基 I（COI），并利用 11 个额外的 GenBank 序列进行了种群遗传分析，以评估种群结构。为了检查形态变异，我们对盾板和背板分别应用了二维地标几何形态测量学，对 148 个和 151 个个体进行了分析。此外，我们还估计了实地的一年生个体密度，以比较不同地点的繁殖响应。我们在四个地点检测到 33 种单倍型，它们属于三个不同的分支，基于适度的种内遗传距离（≥3.5%）。这些分支中的单倍型在分布上没有特定的地点。相比之下，我们确实检测到了外壳形状和形态空间结构的种群间变异，并且一个种群仅基于其独特的背板形态型就可以与其他种群区分开来。这个形态上独特的种群也通过显示最低的平均繁殖密度而与其他种群分化开来。我们的结果表明，尽管 COI 基因的分子变异与韩国的地理区域之间没有关系，但与外壳形态和繁殖响应的地点有关，这表明这种藤壶在新栖息地中具有生态适应性。
