Geographic distribution of Strumigenys louisianae (Hymenoptera: Formicidae)

Abstract

Strumigenys spp. are tiny predatory ants that feed on soil arthropods. Strumigenys louisianae has the broadest geographic distribution of any New World Strumigenys. Here, I compiled >700 site records of S. louisianae to document its biogeography. The known range of Strumigenys louisianae is largely continuous from Argentina to North Carolina (and possibly Virginia and Illinois) and on most major West Indian islands. The occurrence of S. louisianae throughout this region in a wide diversity of habitats makes it difficult to distinguish where it is native and where it has been introduced. The possibility remains that S. louisianae has a very broad native range, but no introduced populations. Alternatively, some isolated S. louisianae populations may be exotic, such as those on the Galapagos Islands, Cocos Island, many West Indian islands, and in Arizona. Genetic analyses are needed to determine where S. louisianae is native and where it is exotic.