Report on the invasive American brackish-water mussel Mytella strigata (Hanley, 1843) (Mollusca: Mytilidae) in Beibu Gulf

Abstract

This study reports the first record of the biofouling mussel Mytella strigata (Hanley, 1843) in Beibu Gulf, China. Phylogenetic analysis based on the mitochondrial DNA cytochrome c oxidase gene sequences demonstrated a close relationship between mussels in Chinese seas and those in Singapore, Venezuela, India, the USA, the Philippines, Brazil, Colombia, Ecuador, and Trinidad. The results of multiple species delimitations showed that the mussel was Mytella strigata. Analysis of the haplotype network indicated that the American brackish water mussel may have invaded China from Colombia or other Asian waters through ships docked in ports or biofouling on the hulls. Mussels attach to oyster shells in large quantities. The minimum shell length of mussels collected in Guangxi Province was 23.9 mm, which exceeded the minimum length for sexual reproduction. The identification of Mytella strigata in Beibu Gulf represents the sixth record of this species from the Indo-Pacific region. In addition, the mussel was also found have invaded Fujian Province. Alien marine species may cause many negative effects and have the potential to harm the invaded ecosystems. Therefore, the distribution of this species within Chinese waters and potential damage caused by this mussel to the ecosystem and economy must be determined. The findings of this study will also provide a reference for formulating management policies for invasive species.