Assemblages of neotropical frugivorous bats display a trophic structure composed of groups of species reflecting diet preferences. The structure is hypothesized to be an ancestral trait, suggesting that very similar diets would be observed throughout a species' range. We examined the frequency of occurrence of seeds in feces of a community of frugivorous bats in Lacandon Forest, México. Using metric multidimensional scaling, we found 3 groups of species, similar to those found in other regions and congruent with phylogenetic groupings, lending support to a historical origin of this structure. However, the diets of some species differed from those observed in other regions, in particular Barro Colorado Island (BCI), Panama. Here, we found species of the tribe Ectophyllini to be specialized on plants of the genus Cecropia, rather than Ficus-specialists as on BCI. This discrepancy can be related to differences in plant composition or in disturbance regimes, and we suggest that Ectophyllini (including Artibeus) are facultative specialists of the genera Ficus and Cecropia rather than strict Ficus-specialists.