The indigenous musical styles of Venezuela are exemplified by groups like Un Sólo Pueblo and Serenata Guayanesa. The national musical instrument is the cuatro. Traditional musical styles and songs mainly emerged in and around the ''llanos'' region, including, "Alma llanera" (by Pedro Elías Gutiérrez and Rafael Bolívar Coronado), "Florentino y el diablo" (by Alberto Arvelo Torrealba), "Concierto en la llanura" by Juan Vicente Torrealba, and "Caballo viejo" (by Simón Díaz).