Which of these fictional cartoon characters was not created by Hanna-Barbera?

The fictional cartoon characters Huckleberry Hound, Yogi Bear, and Snagglepuss were each created by William Hanna and Joseph Barbera (Hanna-Barbera). Respectively, the debut of the first two was in September 1958; the third debuted in September 1959. The fictional cartoon character of Yosemite Sam was not produced by Hanna-Barbera.

Yosemite Sam is a character in the Looney Tunes and Merrie Melodies series of short films produced by Warner Bros. His name is taken from Yosemite National Park in California. He is an adversary of Bugs Bunny who has the archenemy of Elmer Fudd. Fudd will also sometimes face antagonizing situations involving Sam.

Yosemite Sam, in fact, was based on a real person. The American writer and storyboard artist for classic animated cartoon shorts Michael Maltese said that he based Sam on Hollywood film director Friz Freleng. Friz was short guy (Jack Warner always called Chuck Jones and Freleng “Mutt and Jeff” because of their heights). Friz was also red headed, had a mustache, and was notoriously short tempered. It was the animator Friz Freleng who introduced the villain character Sam in the 1945 cartoon "Hare Trigger".

The character Yosemite Sam is really one who loves to use an iconic catchphrase, "I'm the meanest, roughest, toughest hombre that's ever crossed the Rio Grande - and I ain't o namby-pamby!" He certainly became known for using some colorful descriptors in his vocabulary.