A gunman who shot a Staten Island jeweler during a botched heist yesterdaypleaded guilty to robbery conspiracy and weapons charges that could land him in prison for 30 years to life.

Charles Santiago, 26, admitted to shooting Louis Antonelli, 43, as he left a restaurant on April 29, 2008.

The feds believe a Mafia capo ordered Santiago and a crew of robbers to stick up Antonelli, because the jeweler owed the mob money.