ABSTRACT Littorina Férussac, 1822 is an abundant genus of small gastropods found in the upper littoral zone of rocky seashores worldwide. Although ecologically important, shell-based species identification in this genus is challenging due to phenotypic variation in shell morphology and lack of diagnostic characters among morphologically similar species. In this study, we revised the taxonomy of Korean Littorina species using morphological characters (shell and radula) and cox1 mitochondrial DNA sequences for three Korean species: L. brevicula, L. sitkana, and L. horikawai. Results suggest that L. sitkana was erroneously reported as L. kasatka in a previous study. A new record for Littorina horikawai (Matsubayashi & Habe in Habe, 1979), previously unknown from Korea, is described, which can be distinguished from L. sitkana by the presence of alternating white and brown spiral ribs on each whorl. Comparison of the mtDNA cox1 gene sequences shows very low intraspecific variation even between geographically distant populations. A phylogenetic tree supports a close relationship between L. horikawai and L. sitkana, consistent with earlier phylogenetic studies.

中文翻译：

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韩国 Littorina 属（软体动物：腹足纲）的修订

摘要 Littorina Férussac, 1822 是一个丰富的小腹足类属，发现于世界各地岩石海岸的上沿海地区。尽管在生态上很重要，但由于壳形态的表型变异和形态相似物种之间缺乏诊断特征，因此该属中基于壳的物种鉴定具有挑战性。在这项研究中，我们使用三种韩国物种的形态特征（壳和轮辐）和 cox1 线粒体 DNA 序列修订了韩国 Littorina 物种的分类法：L. brevicula、L. satkana 和 L. horikawai。结果表明，在之前的一项研究中，L. sitkana 被错误地报告为 L. kasatka。描述了以前在韩国未知的 Littorina horikawai (Matsubayashi & Habe in Habe, 1979) 的新记录，它可以与 L. sitkana 通过在每个螺纹上存在交替的白色和棕色螺旋肋。mtDNA cox1 基因序列的比较表明，即使在地理上相距遥远的人群之间，种内变异也非常低。系统发育树支持 L. horikawai 和 L. satkana 之间的密切关系，这与早期的系统发育研究一致。