Stichodactyla mertensii, Mertens' carpet anemone (family Stichodactylidae), is the largest carpet anemone in the world, with oral discs potentially reaching 1 m or more in exposed Indo-Pacific reef environments, bearing thousands of short, thick tentacles with distinctive coloration. It hosts the largest diversity of clownfish species of any anemone host, with at least twelve Amphiprion species known to associate with it. Its ecology and physiology have been studied in the context of reef anemone population dynamics and climate vulnerability. Genomic data have been generated for this species and are available in public databases, enabling comparative studies of cnidarian evolution and ecology.