Green mussel Perna viridis (L.) on the Brazilian coast: a fast-spreading invasive species reaching protected areas

Since 1995, the spread of the green mussel Perna viridis (L.) along the South American coast has raised concerns about its potential impacts on coastal communities in vulnerable areas. This study presents updated records of P. viridis along the Brazilian coast and assesses its presence within marine protected areas. Species identification was based on periostracum coloration and mantle papillae morphology, effectively distinguishing P. viridis from the native congener Perna perna (L.). Its presence in lagoon complexes poses significant challenges for the conservation of native species and maintenance of regional biodiversity. We stress the need to assess the balance between predators, parasites, and other ecological components in invaded areas to mitigate the impacts on regional ecology. In-depth studies on the population dynamics of P. viridis must be conducted, assessing nutrient levels in restricted environments and factors influencing the species' attachment to different substrates. Our findings highlight the urgency of implementing effective management strategies and adaptive conservation policies to address the invasion of P. viridis. These policies should focus on preventing further spreading of the species and supporting the sustainability of local estuarine and coastal ecosystems.