Instituto Tecnológico Vale Desenvolvimento Sustentável, Belém, PA, 66055-090, Brazil.
Departamento de Sistemática e Ecologia, Universidade Federal da Paraíba, João Pessoa, PB, Brasil.
Genetica. 2024 Nov 26;153(1):4. doi: 10.1007/s10709-024-00221-4.
DNA barcoding based on COI sequences has been highly informative for the taxonomic assessment of many fish species due to its high rate of species identification. Accordingly, numerous studies have employed this method to encompass species checklists of different areas, assessment of cryptic diversity, biodiversity monitoring, and other applications. Furthermore, most of the success of COI DNA barcoding relies on a comprehensive database (BOLD Systems) that holds sequences and detailed records of millions of species and applies a system (BIN) that clusters short DNA barcodes to generate OTUs. Besides COI, the 16S rDNA has proven to be suitable for the molecular identification of several taxa, and the combination of both markers could be advantageous in investigating species composition in the Neotropics. The family Paralichthyidae comprises over 60 flatfish species. Most of them inhabit tropical areas and remain understudied. Here, we evaluated the diversity of Paralichthyidae species along the Brazilian coast through COI and 16S DNA barcodes. Combining our dataset with BOLD (COI) and GenBank (16S) public records, we conducted tree-based and genetic distance analyses along with BIN-based and species delimitation methods. Our results were consistent for both markers, and we identified eight species of paralichthyids among our samples with high confidence. Interestingly, our analyses indicate several cases where public records assigned to the same species might be sequences from multiple species. Therefore, we provide new records and occurrences and explore important issues regarding misidentification and putative cryptic diversity for several species.
基于 COI 序列的 DNA 条形码技术因其具有较高的物种鉴定率，已被广泛应用于许多鱼类的分类评估中。因此，许多研究都采用这种方法来涵盖不同地区的物种清单、评估隐存多样性、生物多样性监测和其他应用。此外，COI DNA 条形码的大多数成功都依赖于一个综合数据库（BOLD Systems），该数据库拥有数以百万计的物种的序列和详细记录，并应用一种系统（BIN）将短 DNA 条形码聚类以生成 OTUs。除了 COI 之外，16S rDNA 已被证明适用于多个分类单元的分子鉴定，并且这两个标记物的组合在调查新热带地区的物种组成方面可能具有优势。拟鲷科（Paralichthyidae）包含超过 60 种比目鱼。它们大多数栖息在热带地区，研究较少。在这里，我们通过 COI 和 16S DNA 条形码评估了巴西沿海地区拟鲷科物种的多样性。将我们的数据集与 BOLD（COI）和 GenBank（16S）公共记录相结合，我们进行了基于树的和遗传距离分析以及基于 BIN 的和物种界定方法。这两种标记物的结果都是一致的，我们在样本中确定了 8 种拟鲷属鱼类，具有很高的置信度。有趣的是，我们的分析表明，公共记录中分配给同一物种的序列可能来自多个物种。因此，我们提供了新的记录和出现情况，并探讨了几个物种的错误鉴定和潜在隐存多样性的重要问题。
