A key to Central European species of the genus Rhithrogena (Ehemeroptera: Heptageniidae)

Abstract: The genus Rhithrogena Eaton, 1881 comprises more than 100 predominantly Holarctic species. Of the 73 West Palaearctic species, 37 species have been found in Central Europe so far. With the exception of a single case of sibling species and two species having unknown larval stage, larvae can be determined according to 7 formal “species-groups” (R. alpestris – 7 spp., R. hercynia – 5 spp., R. hybrida – 10 spp., R. germanica – 1 sp., R. semicolorata – 9 spp., R. loyolaea – 3 spp. and R. diaphana – 2 spp.) regardless the fact that these groups are artificial and do not reflect true interspecific phylogenetic relationships. Simple distinguishing characters apparent under the light microscope obtained mainly by study of material from the Labe basin are keyed and illustrated. Synomymy of Central European species is summarized.

Key words: Key, species-groups, distinguishing characters, list of species, distribution, synonymy, Ephemeroptera, Heptageniidae, Rhithrogena, Central Europe