Ruellia simplex, the Mexican petunia, Mexican bluebell or Britton's wild petunia, is a species of flowering plant in the family Acanthaceae. It is a native of Mexico, the Caribbean, and South America. It has become a widespread invasive plant in Florida, where it was likely introduced as an ornamental before 1933. 紫花芦莉草, 翠蘆莉, Kencana ungu.