GIANT SIBERIAN FISH

The Chukchi of Siberia will tell you of this piscine colossus.  You will only see it in deep lakes and it can break a boat in two with its jaws.  It is said that the paddle of a boat could be placed between one eye and the other.

That measurement may be an exaggeration, but there may be a huge and uncatalogued piscid in some of Siberia's inland waters.