Officially Cans 'Hey Reb!' Mascot

"Hey Reb!" is officially no more ... UNLV has punted the mascot forever -- but the school is still keeping its "Rebels" nickname.

University president Keith Whitfield made the announcement in a letter to the UNLV community on Tuesday ... saying the cartoon character with confederate ties will be retired for good.

Whitfield said the school currently has no plans to replace the mascot with a new one.

Of course, the decision isn't too surprising ... given the school just removed a famous on-campus statue of "Hey Reb!" back in June.

UNLV hoops legend Isaiah "J.R." Rider praised the decision at the time, telling TMZ Sports, "I think it's the right thing to do personally."

As for the school's…