(Youngina,(Squamata,(Gephyrosaurus,(Diphydontosaurus,(Planocephalosaurus,(Palaeopleurosaurus,((Clevosaurus,(Polysphenodon,Brachyrhinodon)),(Homoeosaurus,(Kallimodon,(Sapheosaurus,((Eilenodon,Toxolophosaurus),(Cynosphenodon,Sphenodon))))))))))));