I do not think anybody still discovers subatomic particles.
Today, it is strings.
Actually there are a whole host of subatomic particles that have been discovered. When we say that there is such a particle as a pion (made from up and down quarks) what we really mean is that there are several pions, of varying mass and spin. So particles are still being discovered today. Few of them seem to contradict the quark model, though some of them DO have odd properties.