Using higher taxa as surrogates of species richness: a study based on 3700 Coleoptera, Diptera, and Acari species in Central-Hungarian reserves

The conservation of biodiversity needs to locate the most diverse sites. Species level is the most often considered taxonomic resolution. However, it is almost impossible to conduct a rapid species level survey of many hyperdiverse and difficult to identify taxa, mainly within arthropods, which are the main components of species richness. I tested whether higher taxa (genus and family) are good surrogates of species richness in three large and usually not surveyed groups in 16 reserves in Central-Hungary: Coleoptera (2415 spp), Diptera (1004 spp), and Acari (288 spp). Species richness of the reserves correlated strongly with both genus and family diversity for all groups. Species numbers also correlated between pairs of the three taxa, but not for genus and family numbers. Therefore, higher taxon diversity is a good surrogate of species diversity, but the diversity of one taxon can indicate the diversity of the other only at the species level.