source: wikipedia https://upload.wikimedia.org/wikipedia/commons/thumb/e/e9/Acropora_pulchra.jpg/640px-Acropora_pulchra.jpg public domain
source: wikipedia https://upload.wikimedia.org/wikipedia/commons/thumb/e/e9/Acropora_pulchra.jpg/640px-Acropora_pulchra.jpg public domain