SANTA FE, New Mexico (Reuters) - Actor Johnny Depp, who plays the American Indian sidekick Tonto in the upcoming film version of "The Lone Ranger," has been made an honorary member of the Comanche Nation, a Native American activist said on Tuesday.

The private ceremony for the 48-year-old actor took place on May 16 at the Albuquerque, New Mexico, home of LaDonna Harris, the president and founder of Americans for Indian Opportunity.

"I had read about him and his Native American heritage so I said to my children around Mother's Day, 'Why don't we adopt him?'" Harris said.

Harris' cousin, who serves as the cultural adviser on the "Lone Ranger" movie being filmed in New Mexico, arranged for a meeting.

"He was adopted into my family," Harris said. "The (Comanche Nation) chairman then recognized that adoption which made him an honorary member of the Comanche Nation tribe."

Depp, whose most recent film release is "Dark Shadows," was given a Comanche name pronounced "Mah Woo May" meaning "shape shifter."

Depp, who comes from Kentucky, has said that he thought his great-grandmother was part Native American, maybe Cherokee or Creek Indian.

Efforts to reach Depp for comment were not successful.

In discussing his role as Tonto, the Lone Ranger's Native American sidekick and source of wisdom, Depp told Entertainment Weekly magazine last year that he wanted to "reinvent" the duo's relationship.