Bassist Paul Hinojos didn't just leave Sparta last week, he also joined the Mars Volta.

On Thursday, Sparta fans learned about the sudden departure of Hinojos through a brief posting on the emo-inspired quartet's Web site, but were left in the dark as to the why behind his unexpected exit. In the online posting, Sparta merely wished Hinojos well, and revealed the group's immediate intentions to carry forth as a trio -- at least until a suitable replacement could be found to fill the void.

This weekend, the impetus behind Hinojos' exodus was no longer a mystery. The Sparta faithful learned Hinojos had accepted an invitation from prog-punk pioneers the Mars Volta, to assume the sound manipulation duties of the late Jeremy Ward, who passed away on May 25, 2003 from an apparent drug overdose.

Hinojos' band-hopping invokes breakup concerns for Sparta's dedicated fans -- though the band's Web site maintains that all is well, and that the remaining members will continue with the recording of the outfit's forthcoming third record -- while the bassist's introduction to the Volta makes that band that much stronger.

Both the Mars Volta and Sparta rose from the ashes of beloved fiery indie punk band At the Drive-In (see [article id="1442235"]"At The Drive-In Suspend Activity, Cancel April Dates"[/article]). Three of that band's five members -- Hinojos, guitarist Jim Ward and drummer Tony Hajjar -- teamed up to launch Sparta, while the group's two most prominent members -- vocalist Cedric Bixler Zavala and guitarist Omar Rodriguez-Lopez -- carried on to forge the Volta (see [article id="1453018"]"Sparta Rise From At The Drive-In's Ashes With EP, Tour"[/article]). The recent addition of Hinojos tips the Drive-In scale in the Volta's favor.

A posting on the Mars Volta's Web site said, "Hinojos' role within the band will initially be confined to the offstage audio acrobatics that Ward had become renowned for," but that he'll "eventually share the stage with his bandmates during live performances."

"My time with Sparta has run its course and simply wasn't fun anymore," the posting quotes Hinojos as saying. Hinojos had been summoned to assist the Mars Volta once before, by filling in for Ward during the group's 2003 tour.

"We've been friends since we were kids, played in bands together for years, and Paul was close to Jeremy," Rodriguez-Lopez said in the statement. "It's always been clear to me that Paul was the only person who'd be appropriate to take Jeremy's place and fill what we feel is an integral role within the band."