Americium is a radioactive element, which does not occur naturally on earth. Therefore it needs to be produced artificially. It was named after the Americas, because it was discovered in America and in the periodic table it is positioned right below europium.
There is no picture of the corresponding element, yet. Urano and Pluton, the rulers of the underworld, are trying to make new monsters through nuclear fusion. They need new monsters to build a clone army in order to take over the world. Unfortunately these experiments fail regularely.