The Urbana man suspected of stabbing, suffocating and dismembering his girlfriend has pleaded not guilty by reason of insanity. Matthew Puccio, 25, entered the plea yesterday in Champaign County court. He was indicted on aggravated murder and other charges in the March death of 21-year-old Jessica Rae Sacco. He could face up to life in prison if convicted. Four other people charged in the case have pleaded not guilty.