Data from: Moth assemblages in Costa Rica rain forest mirror small‐scale topographic heterogeneity

In many tropical lowland rainforests, topographic variation increases
environmental heterogeneity thus contributing to the extraordinary
biodiversity of tropical lowland forests. While a growing number of
studies have addressed effects of topographic differences on tropical
insect communities at regional scales (e.g., along extensive elevational
gradients), surprisingly little is known about topographic effects at
smaller spatial scales. The present study investigates moth assemblages in
a topographically heterogeneous lowland rainforest landscape, at distances
of less than a few hundred meters, in the Golfo Dulce region (SW Costa
Rica). Three moth lineages – Erebidae-Arctiinae (tiger and lichen moths),
the bombycoid-complex, and Geometridae (inchworm moths) – were examined by
means of automatic light traps in three different forest types: creek
forest, slope forest, and ridge forest. Altogether, 6543 individuals of
419 species were observed. Moth assemblages differed significantly between
the three forest types regarding to species richness, total abundance and
species composition. Moth richness and abundance increased more than
four-fold and eight-fold from creek over slope to ridge forest sites. All
three taxonomic units showed identical biodiversity patterns,
notwithstanding their strong differences in multiple eco-morphological
traits. An indicator species analysis revealed that most species
identified as characteristic were associated with either the ridge forest
alone, or with ridge plus slope forests, but very few with the creek
forest. Despite their mobility, local moth assemblages are highly
differentially filtered from the same regional species pool. Hence,
variation in environmental factors significantly affects assemblages of
tropical moth species at small spatial scales.