Underwater surveys by Natural England off Cornwall’s south coast uncovered rare marine species on maerl beds. The discovery includes a tiny red seaweed new to science alongside several species unrecorded in British waters for centuriesThe findings highlight the ecological significance of Cornwall’s maerl beds, slow-growing, coral-like red algae formations that house over 350 surface-dwelling species and form the majority of England’s maerl habitats. First observed in the 1980s by taxonomy expert Professor Christine Maggs, the species was previously too small to analyse. First UK Record (Ulva rigida): The green sea lettuce species was formally confirmed in UK waters for the first time. Natural England officials and seaweed experts emphasise that despite extensive study in British waters, hidden marine ecosystems remain vulnerable.