Two new features of superdeformed (SD) bands in the A190 region emerge from a study of Hg194 with the Gammasphere detector array. A decrease of the dynamic moment of inertia is observed for rotational frequencies Latin small letter h with strokeω0.4 MeV, confirming long standing expectations based on mean field calculations with pairing. Evidence for a small staggering in the SD transition energies is also observed, suggesting the presence of terms with fourfold symmetry in the SD Hamiltonian
