Diversity and composition of Arctiinae moth assemblages along elevational and spatial dimensions in Brazilian Atlantic Forest

When considering Neotropical Lepidoptera for conservation purposes moths are usually neglected because little is known about their biology, ecology and taxonomy. Using light-traps, we sampled moths in the subfamily Arctiinae (Noctuoidea: Erebidae) along an elevational transect (7–927 m asl) on a steep slope of Atlantic Forest in the southern region of Serra do Mar, Brazil. Serra do Mar assemblages clustered according to three elevational zones. We recorded 294 species of Arctiinae in Serra do Mar, and an approach using rarefaction and extrapolation indicated that species richness decreases with increasing elevation, similarly to patterns found in southern Ecuador and Costa Rica, although diversity in Serra do Mar is lower than in southern Ecuador. The elevational transect samples from Serra do Mar were compared with available data for two other biomes. For such comparative analyses, we focused on the tribe Arctiini, for which assemblages were partitioned into Serra do Mar, Interior Atlantic forest and Pampa. The Brazilian Pampa was expected to be less diverse due to low habitat complexity, but it was not possible to explain the higher diversity of Arctiines in Serra do Mar compared to Interior Atlantic Forest. This discrepancy and the probable reasons behind it are discussed, and directions for future research are proposed. Undoubtedly, there is a great need of extensive taxonomical revisions and basic biology research on Arctiines in the Atlantic Forest, Pampa and probably in other tropical and subtropical habitats. These data should be used to improve future biodiversity research and to produce high quality information as a foundation for effective conservation measures.