In 2023, a marine heat wave in the central Red Sea resulted in the bleaching of all monitored sea anemones, leading to the near-total extinction of clownfish populations. Researchers documented a mortality rate of 94-100% for clownfish and 66-94% for anemones across three reefs. This finding contradicts previous assumptions that Red Sea organisms, adapted to naturally high temperatures, would be less affected by climate change. The study highlights the critical temperature threshold of 22 degree heating weeks, beyond which these ancient mutualistic relationships collapse. The alarming mortality rates in the Red Sea starkly contrast with other Indo-Pacific regions, where anemone mortality remained below 3%. The research underscores the need for increased monitoring and conservation efforts, as the survival of clownfish and their anemone hosts hangs in the balance.