This photograph shows the invasive macroalgae Lophocladia lallemandii growing on the dead matte of Posidonia oceanica seagrass in the Mediterranean sea near Mallorca, Spain. The overgrowth of the macroalgae can have negative impacts on the seagrass, which provides an important habitat for many marine species. This photograph highlights the issue of invasive species in marine ecosystems and the need for effective management strategies to mitigate their impacts