Abstract:The eastern keeled mullet ( genus (Mugilidae, Mugilformes), is an economically important coastal fish in China. For a long time in China, the eastern keeled mullet was considered to be , but many lines of research suggested that this was incorrect. To address this problem, we analyzed based on morphological characters and DNA barcoding, and compared it with other fishes in the genus. During October 2013 to December 2014, we collected samples from Chinese coastal waters, including Ningde, Jinjiang, Xiamen, Jinmen, Humen, Zhanjiang, and the Beibu Gulf. The specimens included in this study had the following morphological characteristics:pectoral fin length/body length ratio of 15.0%-18.3% and head length/body length ratio of 22.5%-25.1%, consistent with data reported by Senou (1987) for (14.5%-18.4% and 22.1%-26.9%, respectively), and different from those obtained for (19.8%-23.9% and 27.0%-31.3%, respectively). A partial sequence of the mitochondrial cytochrome oxidase subunit I (COI) gene was used in a phylogenetic analysis. The net genetic distance between recorded at GenBank is 13.11%. A neighbor-joining tree showed that our samples clustered with from GenBank with a genetic distance of 0.08%. However, the genetic distance between our samples and was 13.06%, greater than the threshold for species delimitation. The phylogenetic analysis strongly supported the validity of in China at the genetic level. As a result, we propose that the eastern keeled mullet is really exists in Chinese coastal waters. Although the task of identifying and describing new species is ultimately achieved through comprehensive taxonomic work, DNA barcodes can significantly facilitate this process. The conventional taxonomic workflow, which usually requires the collection of morphological and ecological data, can vary for different taxonomic assemblages (i.e., taxonomic identification of birds and fish require different methods and skills), whereas analysis can be applied in a more or less standardized way across large domains (i.e., all animal taxa). As a result, the identification and description of fish species should combine conventional taxonomic methods such as morphological analysis with molecular identification techniques such as DNA barcoding. Japanese and Chinese ichthyologists have traditionally used the name Mugil carinatus or for a mugilid fish with a keel on its back that is commonly found in these regions, ever since Oshima erroneously identified M. affinis was described by Günther (1861) on the basis of a specimen from Amoy, China. Although his description is detailed, he did not describe a keel on its back. Recently, Song reviewed the Chinese mugilids and used the name Valenciennes, 1836). We think this may explain why for so long. The origin, evolution, patterns of speciation, and unique features of genome divergence among the lineages of this species are topics for further research.