Kerala has rich diversity in freshwater fishes. Being the land of forty four rivers, Kerala has two hundred eighty two species of freshwater fishes. Of this seventy nine species are endemic to the Western Ghats and forty two are endemic to the rivers of this southern state. Exotic fishes of thirteen species also occur in Kerala. National Bureau of Fish Genetic Resources has pointed ten species occurring in Kerala as 'most threatened' in the end of last century. Of this Puntius denisonii and Horaglanis Krishnai are included in the Red List Category of IUCN. Rainbow Trout (Sayippu meen) is an exotic fresh water fish arrived at the Anamudi high ranges in the early years of the twentieth century.