Sam Butera, a saxophonist who helped usher in lounge entertainment in Las Vegas and shared the stage with Louis Prima and Keely Smith, has died. He was 81. Butera died Wednesday morning of pneumonia at Sunrise Hospital in Las Vegas, his daughter Cheryl Butera said.Butera played onstage more than 50 years, most famously as the sidekick of singer and trumpet player Prima and Prima's wife,singer Smith.Butera joined Prima at a lounge gig at the Sahara hotel-casino in 1954, assembling a band called The Witnesses and moving to Las Vegas from his hometown New Orleans with his wife, Vera.Cheryl Butera said her father and Prima were successful because their music was happy and people were looking for cheap entertainment. "I think it did make people want to come into the hotel," Cheryl Butera said. "It set the tone of entertainment in Las Vegas."Butera led The Witnesses until 1975, when Prima fell into a coma. Together, their hits included "Jump Jive an' Wail," "Hey Marie" and "Just a Gigolo/I Ain't Got Nobody." Prima died in 1978. "I never did go in for bebop because I always thought in my mind, people wanted to hear the melody," Butera told the Las Vegas-Review Journal in 2004. "I said, 'Gee, you gotta let people know the song that they're listening to, so they can recall."' Butera didn't stop playing until 2004, after touring, acting and collaborating with other famous entertainers. Butera recorded "Stargazer" with Frank Sinatra in 1976 and appeared in the 1960 movie "Rat Race" with Tony Curtis and Debbie Reynolds.When he quit, Butera said he no longer wanted to travel so much.He also had complications from a heart condition that made flying uncomfortable.The lounge scene in Las Vegas also had changed, with a move toward more high-end nightclubs.Butera is survived by his wife, Vera; children Diane Butera Didier, Cheryl, Sam Jr. and Nick; eight grandchildren and one great-grandchild.Arrangements for a memorial service were pending, Cheryl Butera said.