High turnover of Chrysomelidae (Coleoptera) species in semideciduous forest remnants in an agricultural landscape.

Differences in species composition between sites (β diversity) may be the result of spatial species replacement (turnover) or nestedness (subgroups of species from a more diverse site). In fragmented landscapes, the environmental factors that lead to these differences may be spatially structured. Herein, our objective is to determine if the β diversity of Chrysomelidae (Coleoptera) is due to turnover or nestedness and whether the observed pattern is due to loss of forest cover or spatial processes in forest remnants immersed in a matrix dominated by intense agricultural practice. We used an incidence matrix of 99 species sampled from 16 forest remnants and found that the difference in species composition among the fragments is mostly determined by turnover and that this variation is not explained by forest cover or spatial variables. In regions where high habitat loss has generated landscapes containing small and islated forest fragments, structural features, related both to habitat (area, isolation, shape, etc.) and landscape (land use, landscape heterogeneity, etc.) could predict diversity patterns.