Development of effective conservation and management strategies requires assessments of ecosystem biodiversity status, especially in understudied hotspots of global fish diversity. Coral reefs are important habitats for fishes, with biodiversity hotspots known globally. We present the first data on molecular diversity of fishes of Mischief Reef, the largest atoll in the Nansha Islands. Partial sequences (650 bp) of mitochondrial COI gene (Cytochrome c oxidase subunit I) are used to identify 209 individuals, representing 101 species, referable to 62 genera, 27 families, 8 orders, and 1 class. The most abundant orders are the Perciformes (176 specimens, 84.21%), Tetraodontiformes (13 specimens, 6.22%), and Beryciformes (13 specimens, 6.22%). Mean Kimura 2-Parameter genetic distances within genera, families, and orders are 4.51, 13.90, and 17.63%, respectively. We record Monotaxis heterodon from this region for the first time—a species that may previously have been misidentified as M. grandoculis. In addition, we recognized possible cryptic species of Lethrinus olivaceus based on significantly diverging barcode sequences. Barcode data provide new insights into fish diversity of Mischief Reef, important for developing further researches on this fauna, and for its conservation.

中文翻译：

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美济礁鱼类的DNA条形码——南沙群岛珊瑚礁鱼类群落的鱼类多样性

制定有效的保护和管理战略需要对生态系统生物多样性状况进行评估，尤其是在全球鱼类多样性研究不足的热点地区。珊瑚礁是鱼类的重要栖息地，拥有全球知名的生物多样性热点。我们首次展示了南沙群岛最大的环礁美济礁鱼类的分子多样性数据。利用线粒体COI基因（细胞色素c氧化酶亚基I）的部分序列（650 bp）鉴定了209个个体，代表101种，涉及62属27科8目1纲。最丰富的目是鲈形目（176 个标本，84.21%）、四齿形目（13 个标本，6.22%）和贝氏（13 个标本，6.22%）。属、科和目内的平均木村 2 参数遗传距离为 4.51、13.90 和 17.63%，分别。我们首次记录了来自该地区的 Monotaxis 异齿动物——一种以前可能被误认为 M. grandoculis 的物种。此外，我们基于显着不同的条码序列识别了 Lethrinus olivaceus 的可能隐匿物种。条形码数据提供了对美济礁鱼类多样性的新见解，对于进一步研究该动物群及其保护非常重要。