Linepithema humile, better known as the Argentine ant, is a species of small brown ant : they are about half the size of the classical black garden ant. But that’s not a difference in size that will scare the south american ant and an encounter between these species would and up in a fight and the winner would most probably be the little one giving its aggressiveness. Not only they have a strong temper, but there is many individuals per colony compared to other species and several colonies may work together or at least they do not attack each other (it is called « megacolony ») contrary to other species.

                The spread of the Argentine ant began in 1850 from the Parana River (Argentine) to Madeira (Portugal) and continues today on every continent (except Antarctica). If they are not stopped, they will keep on causing both economic and social damages. Sadly, no efficient treatment to control their expand has been found yet although an eradication program already tried in Santa Cruz Island in California might be useful.