Ichtyfauna of lake Sevan is represented by Salmonidae, Coregonidae and Cyprinidae fish families. Sevan trout (Salmo ishchan Kessler 1877) with its 4 ecological subspecies belongs to Salmonidae fish family: summer bakhtak (S. ishchan aestivalis), winter bakhtak (S. ishchan ishchan), Gegarkuni (S. ishchan gegarkuni) and bojak (S. ishchan danilewski).The representative of Coregonidae family is in the lake Sevan the 1920-1930 acclimatized whitefish (Coregonus lavaretus). Two endemics of the lake belong to Cyprinidae fish family Khrami carp (Varicorhinus capoeta sevangi) and Sevan barbel (Barbus goktschaicus). Early 1980s the crucian carp (Carassius auratus gibelio) was penetrated into the lake Sevan from water systems of Ararat field. Since 1987 two endemic species Sevan Trout and Sevan Barble are included in the Red book of Armenia.