I have been researching the last name "Rubio" and I have come up with the following information:

According to research author Gutierre Tibon in his "Diccionario Etimilogico Comparado de los Apellidos Espanoles, Hispanoamericanos y Filipinos" 1992 Fondo de Cultura Economica, S.A. Mexico. he states the following:

Rojo,