Cnidarians are elegant and dazzling aquatic organisms, but despite their beauty they are known to be a threat in many coastal areas around the world. Several species of cnidaria living in tropical or sub-tropical areas are remarkably dangerous, but many Mediterranean species can also cause serious health problems. Really, cnidarians (sea anemones, corals, medusae) are considered among the most dangerous and venomous organisms, thanks to the occurrence in their tissues of batteries of intracellular capsules (nematocysts or cnidocysts) produced by the Golgi apparatus of specialized cells...