What are some unique indigenous grape varieties found in Spanish wines?

Spain is the land of many indigenous grape species that are the national heritage of the country in winemaking. The grape variety of Graciano, famous for its vibrant color and tartness is used in Rioja together with Tempranillo to make it more complex. Bobal, a native grape of the region Valencia, that have complex and dark red that show well structured tannins. The grape of Mencia, cultivated mostly in Bierzo and Ribeira Sacra, is distinctive in what way, producing refined and beautifully aromatic wines with hints of red fruit and floral touches. These local grape varieties truly represent the diversity of Spain that spans its wine-making tradition.