17. Temnothorax tuberum (Fabricius 1775)

The taxonomy of T. tuberum is still not fully resolved, as it may comprise some cryptic species ( Seifert, 2018). However, it is presently thought to have a very wide distribution across Europe, from the Pyrenees east to Buryatia (Russian Federation) and from the Apennines to Scandinavia ( Seifert, 2018). However, in the past, the name T. tuberum was commonly applied to a very diverse and large array of currently distinct species, which were at most considered as infraspecific forms due to the poor evolutionary understanding of ants’ diversification. There is only an old Sicilian record of T. tuberum from Santa Ninfa in the Belice Valley (De Stefani, 1894), a thermophilous locality below 500 m asl. However, in Sicily we found no true T. tuberum, but two or even more, superficially similar undescribed Temnothorax . Moreover, considering the age of this record, De Stefani (1894) may have named so a species that does not even resemble T. tuberum .