Spain's popular holiday destinations are under threat from a fast-spreading algae. Rugulopterix okamurae is causing concern due to its rapid growth and impact on the beaches across parts of the sun-drenched nation. This Pacific native seaweed has invaded areas in the Atlantic and Mediterranean, completely covering the seabed and releasing plant remains that rise to the surface. The currents then carry the algae to the coast, where it continues to spread over beaches, turning them brown. First