Formicidae, Hymenoptera, Insecta, Arthropoda, Animalia
Range
Southern United States south to Peru and Bahia, Brazil (Lattke 1995). Costa Rica: Pacific lowlands.
Identification
Promesonotal suture absent; scapes just barely reach, but do not distinctly surpass, margin of vertex when laid back; dorsal surfaces of mandibles striate on basal fourth or less, rest smooth and shining; head width across eyes less than 1.0mm.
Notes
Gnamptogenys hartmani was formerly treated as three species: hartmani, nigrifrons, and turmalis (see Lattke 1995, Brown and Kempf 1968).
Scattered observations suggest that the species may be a specialized predator on Trachymyrmex. J. C. Moser observed several colonies in nests of Trachymyrmex in Louisiana (cited in Brown and Kempf 1968). Echols (1964) also reported it as a predator on Trachymyrmex in Louisiana. The type colony of turmalis was found on Barro Colorado Island in Panama, and Brown and Kempf state "it is believed that the ants were raiding a nest of the attine genus Trachymyrmex." Another example of predation on Trachymyrmex is reported below.
In Costa Rica, this species is rarely encountered. I have observed it at three localities: Puntarenas: Curu Wildlife Refuge, 9¡47'N, 84¡55'W, 5m (J. Longino); Sirena, Corcovado National Park, 8¡29'N, 83¡36'W, 5m (J. Longino); 19km S Ciudad Neily, 8¡29'N, 82¡58'W, 20m (J. Longino). The first site is dry forest at the tip of the Nicoya Peninsula; the second and third sites are wet forest on the Osa Peninsula. At Curu I collected a nocturnal forager on the ground surface. At the site near Ciudad Neilly I collected workers in a Winkler sample of sifted leaf litter from the forest floor. At Sirena I observed workers carrying brood in a loose, 3m long column on a rotten log. Dana Meyer, a student working at Sirena, found a colony in the leaf litter, amidst the remains of a Trachymyrmex nest. There were cut-up workers and a cut-up queen of Trachymyrmex, and many wounded Gnamptogenys workers.
Type data
Ectatomma (Parectatomma) hartmani (Wheeler 1915:390). Type worker: USA, Texas: Huntsville.
Literature Cited
Brown, W. L., Jr., and W. W. Kempf 1968. Report on some neotropical ant studies. Papeis Avulsos de Zoologia, Sao Paulo 22:89-102.
Echols, H. 1964. Gnamptogenys hartmani discovered in Louisiana. Annals of the Entomological Society of America 57:137.
Lattke, J. E. 1995. Revision of the ant genus Gnamptogenys in the New World (Hymenoptera: Formicidae). Journal of Hymenoptera Research 4:137-193.
Wheeler, W. M. 1915. Some additions to the North America ant fauna. Bulletin of the American Museum of Natural History 34:389-421.
Page author:
John T. Longino, The Evergreen State College, Olympia WA 98505 USA.longinoj@evergreen.edu