Epizoans on Floating Golden Tide Macroalgae in the Southern Yellow Sea

Golden tide macroalgae have been accumulating in the Southern Yellow Sea (SYS) for several years, causing serious damage to local coastal economy and ecosystems. However, little is known about the environmental and ecological significance of the epizoans drifting on the floating macroalgae. In this study, floating macroalgae collected from four stations were identified as Sargassum horneri. Furthermore, morphological and molecular (based on the Cytochrome C Oxidase Subunit I, COI) identification revealed that the 28 epizoans on the macroalgae consisted of four crustacean (Ampithoe lacertosa, Idotea metallica, Apohyale sp., and Peramphithoe tea). Apohyale sp. and P. tea were found at all stations, while A. lacertosa is found at only one station. The weight range of Apohyale sp., P. tea, I. metallica, and A. lacertosa is 0.0037 similar to 0.0420 g, 0.0057 similar to 0.0304 g, 0.0222 similar to 0.6592 g, and 0.0047 g, respectively. The specific roles of these epizoans in the golden tide in SYS deserve further study. Our results provide a reference for future studies of invasive macroalgae and epizoans.

Automated summary

Golden tide macroalgae in the Southern Yellow Sea have caused significant damage to the local coastal economy and ecosystems. This study identified the floating macroalgae as Sargassum horneri and discovered 28 epizoans, including four crustacean species, on the macroalgae. Further research is needed to understand the role of these epizoans in the golden tide and their ecological significance.