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Dott.ssa Chiara Caruso (Responsible of Tartanet) Dott.ssa Lucia Venturi (President of Regional Park of Maremma) Dott. Sergio Ventrella (Tuscany Observatory of Biodiversity) Anguilla anguilla (Linnaeus, 1758), Anguillidae, Actinopterygii Eel Anguilla Eel Anguilla It is a fish with snake-like body, large and pointed head and a continuous fin from dorsal to anal region of body. It has small pectoral fins to help navigation along river bottoms. Its scales are thin and soft. They are catadromous fish: adult lives in fresh water and migrate to the ocean to spawn. European eels hatch from eggs on the bottom of the Sargasso Sea as leptocephali, leaf-like larvae (Tsukamoto et al. 1998). After hatching, larvae spend a maximum of one year migrating to Europe, or occasionally North America, via ocean currents. The marine larvae metamorphose into glass eels and enter estuarine areas. Glass eels keep on growing (males for 6 to 12 years, females for 9 to 20 years) (Deelder, 1970). After a final metamorphosis, they reach sexual maturity, and migrate from freshwater streams back to the Sargasso Sea to spawn. European eels invest a great amount of energy in reproduction, and die shortly thereafter. Consequently, the female eels give to their offspring only enough food source until hatching. After hatching, the larvae are completely independent and able to find food (Lecomte-Finiger, 1994). European eels distribute nutrients between marine and freshwater ecosystems because they migrate between those two habitats. European eels are both a food source for birds and large predatory fish and a predator of organisms in their ecosystem. European eels also act as a host for the nematode parasite Aguillicola crassu. Deelder, C. 1970. Synopsis of biological data of the eel Anguilla anguilla (Linnaeus, 1758). FAO Fish. Synop., 80: 68. Tsukamoto, K., I. Nakai, W. Tesch. 1998. Do all freshwater eels migrate?. Nature, 396: 635-636. Lecomte-Finiger, R. 1994. The Early Life of the European Eel. Nature, 370: 424-425. Eels are an important food fish. Some species are now farm-raised and eel aquaculture is a fast-growing industry. Unfortunately, they are not bred in captivity. Indeed, young eels are collected from the wild and then raised in various enclosures. In addition, during aquaculture parasites can increase and diffuse into the wild populations. Seafood Watch, a sustainable seafood advisory lists, recommends consumers avoid eating wild eels due to significant pressure on worldwide populations. They are classified as Critically Endangered species in IUCN Red List Muraena helena Linnaeus, 1758 Mediterranean moray Murena The Mediterranean moray has an elongated, eel-like body and can reach a length of 1.5 meters and weigh over 15 kilograms. The skin is slimy and without scales. The dorsal fin begins behind its head and continues to the caudal fin. Pectoral fins are absent, teeth are long and sharp-pointed, the mouth is long and robust and reaches behind the gills. The bite of the Mediterranean moray can be dangerous mainly due to the mildly toxic slime of its skin. The Mediterranean moray inhabits the coastal waters of the Mediterranean Sea and the eastern Atlantic Ocean (from the British Isles to Senegal). It prefers rocky bottoms, at depth from 5 to 80 meters, during the day is hidden in cavities and clefts between rocks and is more active at night. It is a solitary and territorial species and it hunts fishes, crayfishes and cephalopods, but also feeds on dead animals. The Mediterranean moray's reproduction is not well known. They spawn about 60,000 eggs into open water, from which planktonic transparent leptocephali hatch. The skin can be used for leather and it is occasionally used for food. Conservation status in the Red list Category: Least Concern "Muraena helena". IUCN Red List of Threatened Species. Version 2014.3. International Union for Conservation of Nature. Retrieved 15 December 2014.