Diversity Patterns of Plants and Phytophagous Beetles in Sub-Saharan Africa1

Abstract. Species distribution of flowering plants (Angiospermae) and the phytophagous beetle group Monolepta (Chrysomelidae) in Sub-Saharan Africa (south of 17 ° N) are compared based on species numbers per square degree grid. The beetle data comprise all 89 valid species for Africa (21,000 specimens of Afrotropical Monolepta have been currently revised). The plant diversity data are based on 6,269 species with some 330,000 distributional records (10–15 % of all African angiosperm species). Shared centres of species richness of both taxa are geodiverse, montane forests, namely the Albertine Rift, Eastern Arc Mountains, isolated East African volcanoes, montane areas in Cameroon and northeastern parts of a the Republic of South Africa. However, the Cape and the Upper Guinea Region show diverging patterns: plant species richness is higher than the richness of Chrysomelidae. Actual diversity patterns versus sampling artefacts are discussed. Certain mechanisms, like allopatric speciation processes, contribute to a diverse flora and fauna in areas of high geodiversity. Thus, if there is a general and taxon-independent positive relationship between geodiver-sity and species richness, these areas are of explicit value for the conservation of terrestrial biodiversity. Key words. Angiosperms, Chrysomelidae, biodiversity, biogeography, distribution patterns, conservation 1