Regional trends and preliminary results on the local expansion rate in the invasive garden ant, Lasius neglectus (Hymenoptera, Formicidae)

The expansion process of the invasive garden ant, Lasius neglectus in Europe and Asia is described in terms of: a) local expansion through colony growing measured on four supercolonies (Seva, Debrecen, Buda Castle and Budateteny) from two distant and climatically different countries (Spain, Hungary), and b) regional expansion, using data from all published and several new non-native localities. Short, local distance processes (few meters to 89 m year-1), as colony budding, are two to five orders of magnitude smaller than long regional distances (ten km to >1000 km). This suggests direct human intervention in the invasive spread. The regional trend also shows that the invasive garden ant has been quickly and steadily increasing the number of non native localities (77) and countries (14) it has reached during the last 30 years.