Thanks for the information, actually I have found this info already. You are right Diego de Montemayor was son of Miguel de la Garza Montemayor and Clara de Villarreal. Diego got married with Maria Lucia de la Garza in Monterrey on February 6th, 1718. Lucia de la Garza was daughter of Francisco de la Garza Falcon and Juana Garcia Gutierrez.
Thank you however for your interest. By the way I have found that one daughter of Diego and Lucia was Maria Eufemia Montemayor, she born on april 23rd, 1730 and got married ab 1748 with Jose Dionicio Martinez. I haven't found any record of their marriage either Monterrey or Salinas Victoria. According to the registers of christening of their children Eufemia and Dionicio lived at Marin (San Antonio de los Martinez). I guess that probably Dionicio was son of Andres Martinez and Lugarda Benavides, due all the godfathers of Diocicio and Eufemia's children are sons of Andres Martinez and Lugarda Benavides, however I haven found any register for him. I found a Jose Leonicio Martinez, son of Andres Martinez born 1724. But I am not sure if is a miss spelling of the name os it Leonicio is different than Dionicio. I don't know if you can help me with this and I really appreciatte your interest.