Coregonus megalops is a putative species of whitefish, part of the Coregonus lavaretus complex (European whitefish).
[1][2] Its distribution is in Sweden, Finland, and Russia.
[1] In Sweden, the name C. megalops has referred to a form of whitefish known as the blåsik ("blue whitefish").
That is however no more considered a distinct species but a morphotype of Coregonus maraena ("Coregonus maraena morphotype megalops"), and not different from "Coregonus maraena morphotype nilssoni".
[3]