Finding of Arcrtic Charr Salvelinus alpinus (Salmonidae) and Sculpin Cottus cf. poecilopus (Cottidae) in the Verkhnyaya Angara basin Near the Divide with the Lena River System: New Data About the Invasion Routes of the Representatives of Lena Ichthyofauna Into Baikal Basin

In Lake Amut (the Verkhnyaya Angara drainage basin) the third population of Arctic charr Salvelinus alpinus (L.) in Baikal basin was found, a presumed invader from the Lena basin; besides, one more representative of Lena ichthyofauna was recorded—sculpin Cottus cf. poecilopus Heckel. This lake is situated close to the divide with the Pravaya Mama River (the Vitim basin), not far from its main channel. The relief structure of the watershed area, in which Lake Amut is located, indicates high probability of the invasion of Lena species into Baikal basin at this place. Data on morphology, age, growth and diet of Arctic charr from Lake Amut are presented and compared with the data on other charr from Baikal basin. New records are discussed in the context of Pleistocene paleogeography of the Baikal region relevant to the history of its fish fauna formation.