Taxonomy and biogeography of Central European Kybos (Insecta, Hemiptera, Cicadellidae)

The Central European species of the taxonomically difficult Holarctic typhlocybinegenus Kybos are revised. Currently it is impossible to identify females and nymphs. Inaddition the otherwise diagnostic shape of the male genitalia is linked by intermediatesin some morphologically similar nominal species. The second important diagnosticstructure, the male sound apodemes, is not yet fully developed in teneral males, a factwhich was not sufficiently taken into consideration by some authors. The present studyevaluates the morphological variation of the male genitalia and sound apodemes. Femalesand nymphs are investigated for taxonomically relevant characters. The studydid not yield previously unknown characters particularly for the females and nymphsbut suggested that the variation of the male genitalia has previously been underestimated.For this reason K. perplexus Ribaut, 1952 and K. paraltaicus Orosz, 1996 aresynonymised with K. strigilifer (Ossiannilsson, 1941) (new synonymies). The base ofthe female ovipositor is variable within Kybos and separates species groups but doesnot diagnose species. Nymphs vary in leg dimensions and colour forming the samespecies groups as the female genitalia but, again, do not diagnose species. In the cladisticanalysis the female genital characters make the most important contribution totree structure whereas the male genitalia are of less importance, contrary to speciesdiagnoses. It is interesting to note that the cladogram comprises a monophyletic groupof Betulaceae feeders.