  Cyclic dominance between species may yield spiral waves that are known to
provide a mechanism enabling persistent species coexistence. This observation
holds true even in presence of spatial heterogeneity in the form of quenched
disorder. In this work we study the effects on spatio-temporal patterns and
species coexistence of structured spatial heterogeneity in the form of habitats
that locally provide one of the species with an advantage. Performing extensive
numerical simulations of systems with three and six species we show that these
structured habitats destabilize spiral waves. Analyzing extinction events, we
find that species extinction probabilities display a succession of maxima as
function of time, that indicate a periodically enhanced probability for species
extinction. Analysis of the mean extinction time reveals that as a function of
the parameter governing the advantage of one of the species a transition
between stable coexistence and unstable coexistence takes place. We also
investigate how efficiency as a predator or a prey affects species coexistence.
