Specific distinction by allozymic data of sympatric sibling species of the pollen-beetle genus Meligethes (Coleoptera, Nitidulidae)

An allozyme analysis was performed, combined with field data on insect/host-plant associations, in order to clarify taxonomic relationships within the W-Palaearctic Meligethes coracinus complex (Colcoptera, Nitidulidae, Meligethinae). The analysis was focused on the specific distinction of ill. coracinus, ill, matronalis and M. subaeneus, with special regard to the last two species occurring in sympatry, Alternative fixed and unique alleles were scored at several loci. The genetic distances between M. matronalis, M. subaeneus and M. coracinus (0.198-0.572) were in the range of values usually scored between closely related insect species, Genetic data and ecological evidence clearly show that M. matronalis and M. subaeneus, erroneously synonymized in a recent paper, are distinct biological species that frequently occur in syntopy in central and southern Europe, on different larval host plants, although they rarely show synchronous phenology. Their specific differentiation likely occurred during the palaeoclimatic changes of the Plio-Pleistocene ice cycles in southern Europe.