Armored Ants are enemies that appear in Super Mario RPG: Legend of the Seven Stars. They are ants that wear a suit of armor and carry axes and are related to Shoguns. They are also found in Barrel Volcano.
They are weak against Ice moves so Mallow should use his Snowy move against them. Since they are wearing a suit of armor, they are resistant to Fire attacks so Mario should stay away from using his Fire based moves and stick to regular, physical attacks.