"Sergio is often referenced as "Pichilinga" which is the name of a strain of flea (small insect/parasite) in Brazilian/Portuguese jargon. Rios was given the nickname when he was a white belt by one of his senior teammates. Rios started being called Pichilinga due to his sparring style when he stuck to people like glue (or a parasite). He was lanky, wiry strong and the name suited him so well, it followed Rios' career from then on."