Marcel Rodríguez-López

Marcel also played live with the Red Hot Chili Peppers in 2006 during their North American tour (for which The Mars Volta was the support act), contributing bongos to "Hump de Bump" and congas to "Charlie." On the final night of the Amputechture / Stadium Arcadium tour, November 5, 2006, Marcel and the RHCP were joined onstage by Omar for the outro jam which went on for over 15 minutes. Marcel then appeared along with the band for the Gnarls Barkley tour, playing nearly every song of the set, starting with the Dallas show, January 13, through the Sunrise, Florida show on January 31, 2007. Marcel also played clavinet during performances of "Warlocks," which was originally played by Billy Preston on the studio recording of Stadium Arcadium.

He formerly played in the band Thieves of Always, which was led by Ralph Jasso, who was a member of The Mars Volta (led by his elder brother Omar) on tour in 2002. Marcel joined The Mars Volta mid-tour in October 2003 at Omar's request as a percussionist. Since then he had been a constant member of The Mars Volta and the Omar Rodriguez-Lopez Group until TMV's dissolution in 2012, contributing percussion and keyboards. He was also a founding member of El Paso band Zechs Marquise, which included his brothers Marfred on bass and Rikardo on keyboards and trumpet; he initially played keyboards and percussion but switched to drums after the band's original drummer left.

Marcellus Rodríguez-López (born September 29, 1983) is a Puerto Rican multi-instrumentalist musician and younger brother of Omar Rodríguez-López. He is best known as the keyboardist and percussionist of The Mars Volta and the drummer for Zechs Marquise. He also produces electronic music under the moniker Eureka the Butcher.