Checklist of marine fishes in the Beibu Gulf: fish classification, resource protection, and biodiversity challenge

Marine fish diversity in the Beibu Gulf from 2014 to 2022 was analyzed, using various methods including at-sea fisheries resource surveys, fishing port surveys, underwater survey techniques, and data from literature, books, and databases, from which 1 059 fish species across 40 orders, 166 families, and 503 genera were identified. Among them, Acanthuriformes displayed the highest diversity, followed by Carangiformes and Perciformes. Notably, eight alien species were found in the Beibu Gulf. The International Union for Conservation of Nature (IUCN) Red List assessment revealed 51 threatened species, primarily cartilaginous fish. Taxonomic changes affected 88.70% of species due to classification adjustments, misidentifications, and junior synonymy. This study contributed new data of the gulf, including one additional order, six new families, 34 new genera, and 81 new species, emphasizing the dynamic nature of marine ecosystems. Fish diversity in the gulf was relatively lower than the broader South China Sea, attributed to limited habitats and survey methods. Different survey methods, such as gill nets, trap nets, and underwater cameras, yielded varying results. Ocean currents may have transported deep-sea species into the Beibu Gulf, leading to accidental records. Research gaps exist in unexplored areas, warranting further investigation. Therefore, the Beibu Gulf hosts significant marine biodiversity, but taxonomic challenges and undiscovered species require new research and conservation efforts.