European grayling (Thymallus thymallus)
Usually graylings are not found in brackish water, but European grayling from the rivers of Finland often goes out into the Gulf of Bothnia of the Baltic Sea. In the Kara and Pechora Rivers on the western slope of the Polar Urals, the European grayling lives together with West-Siberian grayling.
The scale cover is blue-silver; on the sides, from the edge of the gill covers to the middle of the body, small round black spots are scattered. By the specimens from the rivers of the Western Europe, these spots are found on the head and gill covers. The gill covers are dark gray; the pectoral and anal fins are gray-yellow. On the ventral fin there are 3-6 reddish oblique stripes. By the males during the spawning period over the abdominal fins the pale scarlet spots may appear. In the front part of the dorsal fin, the maroon spots of different sizes are not arranged in clear rows. In its rear part, they become wide vertical stripes running along the rays from the fin edge to its base.
This species is the biggest – in the 19th century in the Traun Lake (Austria) there were graylings weighing up to 6.5 kg!