Ehh no. In school in Argentina you are taught that the whole continent is called America, then you have subcontinents in it (North/central/south), and I would guess other south american countries are the same. If you want to say citizen of the USA in Argentina you would call them yankees.
I can't think of the last time I needed to describe myself as being from the continent, but if you really want to call yourselves Americans, I say go for it. People can call themselves whatever they like.
Still, I can't help but notice Argentinean newspapers using americano to refer to refer to things from the US.