England divers solve mystery in ancient seabeds with tiny red seaweed never seen before

Researchers say a marine mystery that baffled scientists for about 40 years has been solved off the Cornwall coast in England. Natural England’s dive team found a tiny red seaweed species—Ceramium—only a few millimeters wide during surveys along Cornwall’s south coast. Divers collected living fragments, grew them in lab conditions, and used DNA sequencing, which showed the organism is entirely new. BBC filming captured an additional detail: one specimen carried tetrasporangia, reproductive structures not previously documented for the newly identified species. The surveys also turned up other rare seaweeds, while the discovery ties back to Cornwall’s ancient maerl beds.