Superfield actions for N = 2 degenerate central charges

We construct the superfield actions for degenerate (spin-reducing) multiplets of N = 2 extended supersymmetry as integrals over all superspace. This requires the integration over the two available central charges as well. We evaluate the detailed component contributions to these actions and show they are total derivatives with respect to central charge dimensions. The resulting spectrum of the theories are analyzed in four dimensions in terms of various boundary conditions in the higher dimensions and the nature of the integration domain