Features distribution and interoperation differences of the Arctic Grayling Thymallus arcticus (Pall.) in the Lena river basin
New data on the distribution and morphology of the arctic grayling Thymallus arcticus (Pall.) in the downstream of the Lena River basin are presented. Additionally to the near delta area this species has been found in the Lena right tributaries - the Tirekhtyakh and Eastern Khandyga. More extensive spreading of the arctic grayling is likely restricted owing to the press of the autochthonous fauna which is represented by one more species of Thymallus genus - Lena grayling Thymallus sp.