Worldwide Spread of the Yellow-Footed Ant, Nylanderia flavipes (Hymenoptera: Formicidae)
biogeography, Biological invasion, exotic species, Invasive species
Nylanderia flavipes (formerly Paratrechina flavipes), an Asian species, was first found outside its native range in a Philadelphia park in 1939. To evaluate the geographic spread of N. flavipes, I compiled specimen records from >250 sites, documenting its earliest known records for 27 geographic areas (countries and U.S. states), including 7 U.S. states for which I found no previously published reports: California, Connecticut, Delaware, Maryland, New Jersey, Rhode Island, and Virginia. Almost all records of N. flavipes from its native range in East Asia come from sites 30.0°N–44.0°N, with a few records from lower latitudes. In the eastern U.S., N. flavipes records come from a somewhat narrower latitudinal range, 32.5°N–42.4°N (South Carolina to Massachusetts). In areas of the U.S. where it invades, N. flavipes seems to blend into the community like a native species. The only noted impact appears to be the disappearance of Nylanderia faisonensis, an ecologically similar species, with similar nesting sites, colony size, and appearance. In the eastern U.S. north of Washington DC, N. flavipes appears to have largely replaced N. faisonensis. Further south, N. faisonensis continues to dominate.