Wayne Newton's monkey ain't your average Curious George ... cause the teenage girl who says the animal bit her says the injury required medical attention.
TMZ's obtained a pic of the injury allegedly caused by Wayne's Capuchin monkey, Boo. The girl's mother is suing Newton claiming Boo bit her daughter's right wrist 2 years ago while visiting Newton's former estate, Casa de Shenandoah ... a tourist attraction and museum in Las Vegas.
Their attorney, Marc Naron of D.R. Patti & Associates, says the bite broke the girl's skin ... causing it to swell -- and she had to go to a hospital where she got a tetanus shot. The pic, btw, was taken the day after the alleged incident.
We're told the alleged victim, who was 15 at the time, underwent follow-up treatments and was left with a gnarly scar that may be permanent. She claims she underwent counseling because of her fear of animals.
In the lawsuit, the family says Boo was not caged nor on a leash when they visited back in October 2017. Wayne and his wife, Kathleen McCrone Newton, tell us they haven't seen the lawsuit. They add ... their company stopped operating Casa de Shenandoah in July 2017, "due to Wayne's almost dying from a spider bite" -- so they have "no idea what happened in October 2017."