Butterfly Assemblages Differ among Vegetation Types in Southern Amazonia.

Environmental heterogeneity is considered an important factor supporting the evolution and maintenance of biodiversity. At small scales, such heterogeneity is thought to promote species co-existence through an increase in niche opportunities. Amazonia, the largest and most biodiverse rainforest in the world, presents a large number of vegetation types within its territory. Here, we tested the hypothesis that butterfly assemblages differ among five vegetation types at a small scale (less than 1 km2) in a region of Southern Amazonia. The vegetation types studied were forest gap, terra firme, igapó, semi-deciduous forest, and bamboo forest. The richest and most abundant community was in forest gap; igapó was the least rich, but held the second most abundant community and the only one with nine indicator species instead of two or three. Assemblage composition differed among all vegetation types, with the exception of forest gap and bamboo forest. Different light levels, temperatures, humidity, and host plant availability among vegetation types are likely relevant factors influencing these butterfly assemblages. The results suggest that the presence of various vegetation types in the region promotes the coexistence of butterfly species, and that specific threats to each vegetation type should be addressed to conserve the region's biodiversity. [ABSTRACT FROM AUTHOR]