Nudibranchs belong to sea slugs. As all other gastropods, they are slow moving bottom dwellers. They have soft bodies and most of them lack an external protective shell. Their secondary gills are exposed outside, as reflected by their neo-latin/greek name “nudibranch” meaning “nude/naked gills”… To protect themselves from predators many developed toxic or bad tasting glands in the skin, and their bright colors warn predators of their horrible taste.