I'm aware - my point was exactly that - Atlantic salmon and brown trout are in the same genus, whereas pacific salmon and rainbow trout are in a different genus

I'm aware - my point was exactly that - Atlantic salmon and brown trout are in the same genus, whereas pacific salmon and rainbow trout are in a different genus. Certain combinations of varieties of trout and salmon are more closely related to each other than other varieties of trout are to other varieties of trout.