Gnamptogenys hartmani

One record from soil in a banana farm and another from soil in a destroyed Trachymyrmex nest. These ants have on several occasions been reported as predators of Trachymyrmex ants (Echols, 1964:137; Kempf and Brown, 1968:94). J. Longino (pers. comm.) reports from Costa Rican field notes of Dana Myer: “a nest was found found in leaf litter amidst the remains of a Trachymrmex nest and many cut up workers and a queen of the attines were also found along with many wounded Gnamptogenys workers.” Longino has observed this species carrying its brood in a loose 3 m column, fleeing from raiding Eciton. One specimen was taken from the stomach contents of Dendrobates lecomelas. (Lattke 1995)

Identification
A member of the hartmoni complex (in the regularis subgroup of the mordax species group). Superolateral corners of declivitous propodeal face with small lobes or carinae; mandibles triangular to subtriangular; metanotal groove vaguely impressed and posterior nodal face has longitudinal costulae; metacoxal dorsum with lobes; subpetiolar process subquadrate. The study of specimens at hand show colors vary enough to make it an unreliable character for separating species and the same is true for irregularities in the sculpture. Specimens from more southern localities have finer costulation. Also found to vary continously was the length vs. width of the petiolar node, as well as other size indicators. (Lattke 1995)

Distribution
In the United States this species has been collected only three times, twice in Texas (Walker and Brazos Counties) (Mackay and Vinson 1989) and once in Louisiana (Bienville Parish) (Echols 1964). The most reasonable explanation for the isolation of these records is that the species is subterranean and difficult to detect.

Distribution based on Regional Taxon Lists
Nearctic Region: United States. Neotropical Region: Colombia, Costa Rica, Honduras, Mexico, Panama, Peru.



Biology
Echols (1964) discovered four colonies in the nests of the fungus ant Trachymyrmex septentrionalis. The ants "had killed most or all of the Trachymyrmex workers, and were occupying the entire nest. Ten nearby nests of T. septentrionalis with deteriorating fungus gardens were devoid of workers and brood, presumably as a result of action by G. hartmani. However, there were many active unmolested nests in the area. The G. hartmani colonies were all observed on an area of about one acre." A captive nest fed on larvae of T. septentrionalis, and did not eat fungus from the garden or adult Trachymyrmex that were killed by stinging.

Nomenclature

 *  hartmani. Ectatomma (Parectatomma) hartmani Wheeler, W.M. 1915b: 390 (w.) U.S.A. Brown, 1961b: 69 (q.); Wheeler, G.C. & Wheeler, J. 1964b: 450 (l.). Combination in Gnamptogenys: Brown, 1958g: 228. Senior synonym of nigrifrons, turmalis: Lattke, 1995: 169.
 * nigrifrons. Ectatomma (Gnamptogenys) nigrifrons Borgmeier, 1948a: 199, figs. 24, 25 (w.q.) PERU. Combination in Gnamptogenys: Brown, 1958g: 228. Junior synonym of hartmani: Lattke, 1995: 169.
 * turmalis. Gnamptogenys turmalis Kempf & Brown, 1968: 93 (w.) PANAMA. Junior synonym of hartmani: Lattke, 1995: 169.