Thymallus thymallus
species of fish
Thymallus thymallus, harjus, the grayling or European grayling, is a species of freshwater fish in the salmon family Salmonidae. 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, and Balkans on the south-east, 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.
Description
The grayling grows to a maximum recorded length of 60 cm (24 in) and a maximum recorded weight of 6.7 kg (15 lb). 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, such as Eurasian minnows. 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.
Begin with the source’s own compact description: “Thymallus thymallus” is species of fish. The dossier treats that line as a proposition to test through Thymallus, thymallus and species, not as a finished interpretation.
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This entry incorporates text from “Thymallus thymallus” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.