Geographic distribution of Gnamptogenys hartmani (Hymenoptera, Formicidae), an agro-predator that attacks fungus-growing ants

Gnamptogenys hartmani is a specialist predator that attacks colonies of fungus-growing ants. To examine the biogeography of G. hartmani, I compiled specimen records of G. hartmani from 36 sites, and records of Gnamptogenys bruchi (a possible junior synonym) from seven sites. Records of Gnamptogenys hartmani ranged from Lucky, Louisiana (32.2°N) in the north to Villa Nougues, Argentina (26.9°S) in the south. If G. bruchi proves to be a synonym of G. hartmani, this would extend the known range as far south as Alta Gracia, Argentina (31.7°S). In the US, G. hartmani populations are known only from Texas and Louisiana, yet there is much apparently suitable habitat along the Gulf coast of Alabama, Mississippi, and Florida. Given the remarkable scarcity of G. hartmani records throughout its known range, it remains possible that G. hartmani populations occur all along the Gulf coast of the US, but have been overlooked.