Wetterer, J.K.

Worldwide spread of the stigma ant, Pachycondyla stigma (Hymenoptera: Formicidae)

The stigma ant, Pachycondyla stigma (Fabricius, 1804), is an inconspicuous forest species that generally nests in and under rotten logs and feeds on termites. This species has an extensive range in both the New World and Old World tropics, but there has been disagreement on where P. stigma is native. To evaluate its known distribution and consider hypotheses on its native range, I compiled and mapped records of P. stigma from > 600 sites. I documented the earliest known P. stigma records for 55 geographic areas (countries, island groups, major West Indian islands, and Us states) including several for which I found no previously published records: Antigua, Montserrat, Nevis, St Kitts, St Lucia, and Tonga. Pachycondyla stigma shows characteristics of a native species throughout its range in both the New World and Old World, with near continuous distributions in intact forest habitats. The earliest records of P. stigma come primarily from the Neotropics; before 1900, there were published Neotropical records from Colombia, Costa Rica, Mexico, Bolivia, Venezuela, Guatemala, Panama, St Vincent, and Cuba, but only one published record from the Old World (Aru Island, Indonesia). Although P. stigma has relatives in both the Neotropics and Australia, its closest known relative is from Central America. Thus, the weight of evidence indicates that P. stigma originated in tropical South and Central America. Genetic analyses are needed to determine whether the native range of P. stigma also includes the West Indies and Florida.

Open access, licensed under CC BY 4.0. © 2012 The Author(s).

Biogeography, biological invasion, exotic species, invasive species.