An analysis of morphometric, allozymic and ecological data gives clear cues of the presence in southern Europe and the Near East of a so far not recognised species of the pollen-beetle genus Meligethes Stephens, previously widely confused with the common and widespread M. coracinus Sturm. Re-examination of the type material allowed the authors to discover that this 'new' taxon was originally described by Ganglbauer (1899) as M. coracinus var. aenescens (nec M. aenescens Fairmaire, 1875), later considered a mere synonym of M. coracinus. This taxon is here resurrected at a specific rank, redescribed, and renamed Meligethes erysimicola Audisio & De Biase, nom. n. The two species are also compared with the closely related Meligethes motronalis Audisio & Spornraft, 1990, a monophagous species strictly associated with Hesperis motronolis L. (Brassicaceae). M. erysimicola is an oligophagous species, strictly associated at larval stage with several members of the plant genus Erysimum L. (Brassicaceae), while M. coracinus is a more polyphagous species, developing mostly on Brassica spp., Sinapis spp., Barbarea spp. and Sisynibrium spp. (Brassicaceae). Waiting for the final results of further molecular and ecological researches concerning the same subject, an updated taxonomical outline of the Meligethes coracinus species-complex is also reported, and a provisional key to identification of species and included sub-complexes, is finally given.