Extra gauge symmetry for extra supersymmetry

It is shown that the extra supersymmetry of tensionless superstring and super p-brane is accompanied by the presence of new bosonic gauge symmetries. It permits to use composed coordinates encoding all physical degrees of freedom of the model and invariant under these gauge symmetries and the enhanced κ-symmetry. It is proved that the composed gauge invariant coordinates coincide with the components of symplectic supertwistor realizing a linear representation of the hidden OSp(1,2M) symmetry of the super p-brane Lagrangian. A connection of the presented gauge symmetries with massless higher spin gauge theories and a symmetric phase of M/string-theory is discussed.