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The grayling (''Thymallus thymallus'') is a species of freshwater fish in the salmon family Salmonidae. Native to the Palearctic ecozone, the grayling is widespread throughout northern Europe, from the United Kingdom and France to the Ural Mountains in Russia. While it was introduced to Morocco in 1948, it does not appear to have become established there. == Attributes == The grayling grows to a maximum recorded length of and a maximum recorded weight of . Of typical ''Thymallus'' appearance, the grayling proper is distinguished from the similar Arctic grayling (''T. arcticus arcticus'') by the presence of 5–8 dorsal and 3–4 anal spines, which are absent in the other species; ''T. thymallus'' also has a smaller number of soft rays in these fins. Individuals of the species have been recorded as reaching an age of 14 years. The grayling prefers cold, clean, running riverine waters, but also occurs in lakes and, exceptionally, in brackish waters around the Baltic Sea. Omnivorous, the fish feeds on vegetable matter, as well as crustaceans, insects and spiders, molluscs, zooplankton, and smaller fishes, including Eurasian minnows and yellow perch. Grayling are also prey for larger fish, including the huchen (''Hucho hucho''). With the Arctic grayling, ''T. thymallus'' is one of the economically important ''Thymallus'' species, being raised commercially and fished for sport. The grayling is a protected species listed in appendix III of the Bern Convention. It has become critically endangered in the Baltic Sea. The term "grayling" is often used to refer generically to the ''Thymallus'' species, and ''T. thymallus'' is sometimes called the European grayling for clarity. There are many obsolete synonyms for the species. The generic name ''Thymallus'' derives from the Greek θύμαλλος, "thyme smell", a name derived from the fragrance of wild thyme that freshly caught graylings are believed to smell similar to. ''Thymallus thymallus'' is the type species of its genus. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Grayling (species)」の詳細全文を読む スポンサード リンク
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