  We investigate the decay modes of pentaquark baryons for both the
antidecuplet and the octet states, which were recently claimed by Close and
Dudek to be potentially narrow due to a hidden selection rule. We discuss how
ideal mixing between the pentaquark octet and antidecuplet states can be
related to the OZI rule, which also naturally leads to certain selection rules
in the pentaquark decays. We then introduce a tensor representation for the
pentaquark states, and present the possible decay modes for both the unmixed
and ideally mixed pentaquark octet and antidecuplet states. The exclusive decay
modes can be used to experimentally search for the other pentaquark states.
