Our research examined the effect of Azteca sericeasur, a keystone arboreal ant, on the decomposition of leaf litter of the shade tree, Inga micheliana, in coffee agro-ecosystems. This interaction is important in understanding the spatial heterogeneity in decomposition. We hypothesized that A. sericeasur could affect leaf litter decomposition by excluding other ants, which could release decomposers, like collembolans, from predation pressure. Determining the relative strengths of these interactions can illuminate the importance of A. sericeasur in decomposition and nutrient cycling processes.

We assessed the ant and arthropod communities surrounding 10 pairs of trees, where each pair included one shade tree with an established A. sericeasur nest. Tuna baits were used in conjunction with pitfall traps to assess the ant and arthropod community, and litterbags with I. micheliana leaf litter were used to assess decomposition. The species richness of ants did not change in proximity to A. sericeasur nests, though the ant communities were distinct. Abundance of collembola and community composition of other invertebrates did not change with the presence of an A. sericeasur nest and there were no differences in leaf litter decomposition rates. This contradicts past studies that suggests A. sericeasur reduces species richness in its territory. We suggest that other ants may avoid A. sericeasur by moving within and beneath the leaf litter. Our results indicate there is no net effect of A. sericeasur on leaf litter decomposition.

The data was collected using 3 methods -- tuna baiting, pitfall traps and litterbags. Site data was taken at paired sites and is included in the data set. Methods are described in full in the manuscript.

Tuna baits were used to describe the ant community. The full list of morpho-species is given in the manuscript's supplementary material. Abbreviations are used in the dataset.

Pitfall traps were sorted to order and ants were described to morpho-species. Again, abbreviations are used, but the full list is given in the supplementary material.

Litterbags with Inga micheliana litter were in the field for a year.