Ricardo Vieira is one of the founders of Checkmat along with his brother Leo Vieira. Also known as "Rico", Vieira has his headquarters in Rio de Janeiro near Copacabana beach - his gym is literally a few blocks from the water which makes training that more pleasurable since you can go for a dip after class.
Rico is famous for having a very versatile open guard and many of his students pride themselves on using this position often. The reverse de la riva is especially useful when your opponent is a speed-passer and you don't have much time to properly re-guard, so the reverse de la riva gives you a chance to grab on what little you can and reverse the situation - give you an offence. Below are two simple yet effective variations that Rico likes to use, demonstrating on his student, and top world competitor, Jackson Sousa.