Tapping a black belt is one of the toughest things to do in MMA. Off the top of my head, I can only think of BJ Penn (KenFlo, Stevenson (might have been a brown belt at the time), and Hughes, who I'll talk about in a bit), Jones (Machida and Vitor), and Hughes (only BB he "technically" submitted was Almeida, but he TKOed BJ from a mounted crucifix and could have broken Royce's arm, but decided to pound him out instead out of respect). Hughes is also the only guy to have tapped GSP, although GSP didn't have his BB when that happened. I'm sure I'm missing a few...who are they? And who should get credit as submission artists for beating guys with great grappling who might not have been formally awarded a black belt?
Also, I was only thinking of BJJ blackbelts, but feel free to include Sambo, Judo, Gaidojutsu, or black belts in whatever other grappling art is out there, let's get creative.
Rousimar Palhares - Flavio Luis Moura, David Branch, Lucio Linhares, Fabio Nascimento, Mike Massenzio Masakazu Imanari - Jorge Gurgel, Renato Tavares, Mike Brown*, Hiroyuki Abe, Jean Silva, Hiroshi Umemura, Kenji Osawa*, Masahiro Oishi* Satoru Kitaoka - Kurt Pellegrino*, Fabricio Monteiro, Kuniyoshi Hironaka Shinya Aoki - Jason Black, Joachim Hansen, Kuniyoshi Hironaka(kinda) * - may not be black belt or have been black belt at the time
Interesting -- looks like a lot of MMA BBs weren't prepared for leglocks, which makes sense because they're illegal in a bunch of grappling tournaments. I know Palhares and Imanari are leglock specialists, and IIRC Aoki got hellboy with a leglock.
Kurt Pellegrino - Junior Assuncao, Fabricio Camoes Nate Diaz - Kurt Pellegrino, Junior Assuncao, Alvin Robinson, Jim Miller Anderson Silva - Travis Lutter, Roan Carneiro(punches)
Gogo Plata in the 1st fight, armbar in the third fight. But you are correct, a lot of BJJ guys do get tapped with leg locks.
Didn't get his purple belt until after the Maia fight believe it or not but Maia did tap Fabio Nascimento who was a black belt.
Kazushi Sakuraba - Gilles Arsene*, Shannon Rich*, Marcus Silveira, Royler & Renzo Gracie Carlos Newton - Jose Pele*, Pat Miletich*, Eric Paulson* Matt Lindland - Travis Lutter, Fabio Leopoldo