7. Lasius (Lasius) niger (Linnaeus 1758)

As in the case of L. alienus described above, the nature of L. niger has been the subject of severe confusion over the decades and was finally clarified about 30 years ago (Seifert 1991; 1992; 2020a). As a result, records from Baroni Urbani (1964a) should be considered unreliable (even more so since they refer to a ‘transitional form’ between L. alienus and L. niger). The only recent Sicilian records of L. niger were published by Li Vigni (2014); however, they were based on misidentified specimens of L. casevitzi (F. Rigato, pers. comm.). We believe L. casevitzi to be a possible candidate of past confusion with L. niger in Italy: despite being closely related to L. paralienus Seifert, 1992, which has historically been confused with L. alienus and not with L. niger, L. casevitzi possess a higher number of erect setae on various key areas resembling L. niger. Overall, L. niger is a Palearctic species not particularly frequent in the Mediterranean, sometimes existing in isolated introduced populations (Seifert, 2018; 2020a), and its whole distribution in Italy should be revised.