MOLECULAR REEXAMINATION OF THE TAXONOMY OF OCHTHEBIUS (CALOBIUS) (COLEOPTERA, HYDRAENIDAE) FROM THE MEDITERRANEAN AND MACARONESIAN REGIONS

The classification of Ochthebius (Calobius) is revised using isozyme a nalysis combined with a preliminary morphological study of population samples from 69 Mediterranean and Macaronesian localities. Seven taxa are recognized, including 3 new taxa, provisionally designated as Ocht hebius species A from Italy O. heeri subspecies A from the western Can aries, and Ochthebius species B from Israel. Ochthebius heeri Wollasto n, 1854 is raised from synonymy with O. quadricollis Mulsant, 1844. On the basis of the descriptors used, as well as on the absence of gene exchange in sympatric areas, specific rank is assigned to Ochthebius q uadricollis, Ochthebius species A and O. brevicollis, whose ranges sho w overlapping areas. For the allopatric taxa Ochthebius heeri heeri an d O. heeri A, Ochthebius species B, O. brevicollis brevicollis and O. brevicollis steinbuehleri, specific or subspecific ranks were assigned mainly on the basis of their degree of genetic differentiation. A bio geographical hypothesis on the origin of the 7 taxa is proposed.