High-order Discontinuous Galerkin Methods (DGM) are now routinely used for simulation of wave propagation, especially for geophysic applications. However, to fully take advantage of the high-order space discretization, it is relevant to use a high-order time discretization. Hence, DGM are classicaly coupled with ADER schemes, which leads to high-order explicit time schemes, but requires the introduction of auxiliary unknowns. The memory can thus be considerably cluttered up. In this work, we propose a new high order time scheme, the so-called Nabla-p scheme. This scheme does not increase the storage costs since it is a single step method which does not require the storage of auxiliary unknowns. Numerical results show that it requires less storage and less computational costs than the DG-ADER scheme for a given accuracy.