  Decay or annihilation products of superheavy dark matter (SHDM) could be
responsible for the end of the Ultra-High Energy Cosmic Ray (UHECR) spectrum.
In this case, the south array of the Pierre Auger Observatory should observe in
the future a significant anisotropy of UHECR arrival directions towards the
galactic center. Here we use the already existing data of the SUGAR array to
test this possibility. If decaying SHDM is distributed according a
Navarro-Frenk-White (NFW) dark matter profile with core radius R_c=15 kpc and
is responsible only for UHECRs above 6*10^{19} eV, i.e. the AGASA excess, then
the arrival directions measured by the SUGAR array have a probability of ~10%
to be consistent with this model. By contrast, the model of annihilating SHDM
is disfavoured at least at 99% CL by the SUGAR data, if the smooth component of
the DM dominates the signal.
