Updating the taxonomy and distribution of the European Osmoderma, and strategies for their conservation (Coleoptera, Scarabaeidae, Cetoniinae)

Results of a molecular analysis on the European hermit beetles (the Osmoderma eremita species-complex), recently published in a companion paper, are shortly discussed and commented. These results indicate a clear-cut distinction between two clades. The first one includes the W-European O. eremita Scopoli, 1763, and the two Italian endemic taxa O. italicum Sparacio, 2000 and O. cristinae Sparacio, 1994, from southern peninsular Italy and Sicily, respectively. The second one includes the widespread E-European O. barnabita Motschulsky, 1845 (nom. resurr.), and the southern Balcanic O. lassallei Baraud & Tauzin, 1991 from Greece and European Turkey. Within the two clades, molecular data well support a specific rank for O. lassallei and O. barnabita on one side, and of O. eremita and O. cristinae on the other side, while the taxo-nomic position of O. italicum, more closely related with O. eremita, is still uncertain, waiting for analysis of additional specimens of this very rare taxon. Current geographical distribution, interspecific genetic diversification, and relatively low levels of intraspecific genetic divergence in O. eremita sensu stricto, are hypothesized to be the result of multiple speciation events (mainly occurred in refugial forest areas of the Italian and Balkan peninsulas and Sicily before and during the Pleistocene glacial peaks), followed by fast post-glacial northward and westward expansion of some species. The need of further genetic data on the rare and threatened hermit beetle species and the importance of more detailed information on their distribution ranges are emphasized and discussed, in order to plan conservation strategies in the near future. An updated worldwide checklist of the species of the genus Osmoderma is finally presented.