A press release from the Karlsruhe Institute of Technology states that experiments have shown that all fermions are known; all matter particles are known. No new ones are expected.
But real theoreticians do not care about experiments. Real theoreticians are those of the IAS in Princeton, where all dream to do as well as Einstein. A well-known emulator is Arkani-Hamed. In his latest talk, he talks about many new fermions. For example, he knows all about "gluinos", his favorite fermions.
There is a good thing about giving a dream a name: it starts existing. Gluinos are as real as Mickey Mouse. Neither exists; but you can make a living with both.
This is what many Einstein emulators are doing: selling Mickey Mouse stories. What a difference to Einstein himself.