The grayling (Thymallus thymallus) is a species of freshwaterfish in the salmonfamilySalmonidae. It is the only species of the genus Thymallus (the graylings) native to Europe, where it is widespread from the United Kingdom and France to the Ural Mountains in Russia, but does not occur in the southern parts of the continent. It was introduced to Morocco in 1948, but it does not appear to have become established there.