Isidro Lopez ( May 17 1929 - August 15 2004) was an American tejano singer and bandleader . Isidro Lopez was a legendary figure in the Mexican-American community. He helped pioneer the genre known as Tejano music, his contributions making him the local equivalent of Elvis Presley in rock'n'roll and Bill Monroe in bluegrass. Tejano is Spanish for Texan, and some Mexican-Americans describe themselves as Tejanos. The music Lopez played was described as Tejano because of his ability to mix traditional Mexican music with elements of pop