Spanish shawl nudibranch on kelp off Santa Catalina Island, California, USA

© WaterFrame/Alam

One stylish slug

Today we're meeting a member of the group of sea slugs called the nudibranchs (rhymes with thanks), known for their unique, often complex shapes and bright neon colours that help discourage predators. The Spanish shawl's fiery orange mane is made up of tendrils called cerata that act as gills. But it also retains venom from the slug's prey - sea anemones - treating any would-be devourers to a painful sting. Should a ravenous starfish disregard these defences and get too close for comfort, the Spanish shawl has a Plan B: By flapping its body like a gelatinous wing, the nudibranch can flutter into open water and make its escape.