Environmental productivity, i.e., the amount of biomass produced by primary producers, belongs among the key factors for the biodiversity patterns. Although the relationship of diversity to environmental productivity differs among studied taxa, detailed data are largely missing for most groups, including insects. Here, we present a study of moth diversity patterns at local and regional scales along a continent-wide gradient of environmental productivity in southern African savannah ecosystems. We sampled diversity of moths (Lepidoptera: Heterocera) at 120 local plots along a gradient of normalized difference vegetation index (NDVI) from the Namib Desert to woodland savannahs along the Zambezi River. By standardized light trapping, we collected 12,372 specimens belonging to 487 moth species. The relationship between species richness for most analyzed moth groups and environmental productivity was significantly positively linear at the local and regional scales. The absence of a significant relationship of most moth groups' abundance to environmental productivity did not support the role of the number of individuals in the diversity-productivity relationship for south African moths. We hypothesize the effects of water availability, habitat complexity, and plant diversity drive the observed moth diversity patterns.

Center for Theoretical Study Charles University Prague and the Czech Academy of Sciences Jilská 1 11000 Prague Czech Republic

Department of Zoology Faculty of Science University of South Bohemia Branišovská 1760 37005 České Budějovice Czech Republic

Departments of Ecology and Zoology Faculty of Science Charles University Viničná 7 12844 Prague Czech Republic

Institute of Entomology Biology Centre Czech Academy of Sciences Branišovská 31 37005 České Budějovice Czech Republic

Institute of Vertebrate Biology The Czech Academy of Sciences Studenec 122 67502 Koněšín Czech Republic

Nicholas School of the Environment Duke University 9 Circuit Dr Durham NC 27710 USA

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