Twin Ants? I haven't heard of them, but they must be a secret character you get fromMinotchi or Mushibatchi, Kat's chart doesn't make it quite clear:http://www.mimitchi.com/gif/moricht3.gif
You know that on Tamagotchi Angel/ Angelgotch you can get the Twin Angels, FutagoTenshi? It must be the equivalent.
Oh, and the growth chart you posted gave me an "FORBIDDEN 403" when I clicked it.