found both in the rivers of the Amazon basin and in the coastal waters of South America. The Amazonian manatee (Trichechus inunguis), also known as "seacow", is found in the northern Amazon River basin and its tributaries. It is a mammal and a herbivore. Its population is limited to freshwater habitats, and, unlike other manatees, it does not venture into saltwater. It is classified as vulnerable by the International Union for Conservation of Nature. The Amazon and its tributaries are the main habitat of the giant otter (Pteronura brasiliensis). Sometimes known as the "river wolf," it is one of South America's top carnivores. Because of habitat destruction and hunting, its population has dramatically decreased. It is now listed on Appendix I of the Convention on International Trade in Endangered Species (CITES), which effectively bans international trade. Reptiles The Anaconda is found in shallow waters in the Amazon basin. One of the world's largest species of snake, the anaconda spends most of its time in the water with just its nostrils above the surface. Species of caimans, that are related to alligators and other crocodilians, also inhabit the Amazon as do varieties of turtles. Birds Fish The Amazonian fish fauna is the centre of diversity for neotropical fishes, some of which are popular aquarium specimens like the neon tetra and the freshwater angelfish. More than 5,600 species were known , and approximately fifty new species are discovered each year. The arapaima, known in Brazil as the pirarucu, is a South American tropical freshwater fish, one of the largest freshwater fish in the world, with a length of up to . Another Amazonian freshwater fish is the arowana (or aruanã in Portuguese), such as the silver arowana (Osteoglossum bicirrhosum), which is a predator and very similar to the arapaima, but only reaches a length of . Also present in large numbers is the notorious piranha, an omnivorous fish that congregates in large schools and may attack livestock. There are approximately 30 to 60 species of piranha. The candirú, native to the Amazon River, is a species of parasitic fresh water catfish in the family Trichomycteridae, just one of more than 1200 species of catfish in the Amazon basin. Other catfish 'walk' overland on their ventral fins, while the kumakuma (Brachyplatystoma filamentosum), aka piraiba or "goliath catfish", can reach in length and in weight. The electric eel (Electrophorus electricus) and more than 100