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Abstract：
The broad global distribution of freshwater clams belonging to the genus Corbicula is driven by multiple hermaphroditic lineages. These lineages, characterized by shared morphological traits and phenotypic plasticity, pose challenges to morphological identification. Genetic markers, such as the mitochondrial COI gene, play a crucial role in delineating these lineages and their ranges. Morphotypes represent observed phenotypic variations, while lineages are defined based on genetic markers. Here, we comprehensively review Corbicula\'s distribution in Argentina, discriminate extant lineages based on both morphological and genetic (COI) data, and describe variations in internal and external morphologies using 15 Argentine populations. Genetic analyses identified two mitochondrial lineages: the AR morphotype (FW5 haplotype) and CS morphotype (FW17 haplotype). Strikingly, despite having similar vectors, origins, and invasive stages, Corbicula lineages exhibit virtually segregated distributions. However, mitochondrial haplotypes are found in sympatry mainly in northeastern Argentina where individuals with intermediate morphotypes exist, suggesting the presence of hybrids due to maternal genome retention. These findings contribute to the clarification of the identity and distribution of Corbicula lineages in Argentina, where the genus has been found for over half a century. Similar studies are needed in other areas to better understand the invasion patterns of this successful and adaptable group.
摘要：
属于Corbicula属的淡水clam的广泛全球分布是由多个雌雄同体谱系驱动的。这些血统，具有共同的形态特征和表型可塑性，对形态学鉴定提出了挑战。遗传标记,比如线粒体COI基因，在划定这些谱系及其范围中起着至关重要的作用。形态型代表观察到的表型变异，而谱系是根据遗传标记定义的。这里,我们全面回顾了Corbicula在阿根廷的分布，根据形态和遗传(COI)数据区分现有谱系，并使用15个阿根廷人口描述内部和外部形态的变化。遗传分析确定了两种线粒体谱系：AR形态型（FW5单倍型）和CS形态型（FW17单倍型）。引人注目的是，尽管有相似的向量，起源,和侵入性阶段，Corbicula谱系几乎表现出隔离的分布。然而,线粒体单倍型主要在阿根廷东北部发现，那里存在中间形态型个体，表明由于母体基因组保留而存在杂种。这些发现有助于澄清阿根廷Corbicula谱系的身份和分布，该属在那里已经发现了半个多世纪。在其他领域需要进行类似的研究，以更好地了解这个成功和适应性强的群体的入侵模式。
