Phylum Porifera and Cnidaria -- Clinical and Therapeutic Aspects of Envenomations Caused by Sponges and Jellyfish -- Phyla Molluska: The Venom Apparatus of Cone Snails -- Venomous Marine Fish: Evolution of the Venoms. Condrichthyes (Cartilaginous Fish) -- Venomous Marine Fish: Osteicthyes (Bony Fish) -- Venomous Freshwater Fish: Catfish and Freshwater Stingrays -- Toxins Produced by Marine Microorganisms: A Short Review -- Toxins Produced by Marine Invertebrate and Vertebrate Animals: A Short Review -- Pufferfish Poisoning and Tetrodotoxin -- Ciguatoxin and Ciguatera -- Saxitoxin and Other Paralytic Toxins: Toxicological Profile -- Brevetoxins: Toxicological Profile -- Okadaic Acid and Other Diarrheic Toxins: Toxicological Profile -- Domoic Acid and Other Amnesic Toxins: Toxicological Profile -- Azaspiracid Toxins: Toxicological Profile -- Spirolides and Cyclic Imines: Toxicological Profile -- Palytoxins: Toxicological Profile -- Effects of Cyanotoxins: Sea and Freshwater Toxins -- Microcystins: Toxicological Profile -- Jellyfish Venom and Toxins : A Review -- Equinatoxins: A Review -- Intoxications Caused by Saxitoxin, Shellfish, and Other Neurotoxins -- Phylum Echinodermata e Annelida: Sea Urchins, Starfish and Sea Cucumbers, and Marine Worms -- Instrumental Methods for Paralytic Shellfish Toxins -- Immunomodulatory Properties of Sea Cucumber Triterpene Glycosides -- Miscellaneous Marine Toxins of Medical Significance. .