Atta colombica

Distribution based on Regional Taxon Lists
Neotropical Region: Colombia, Costa Rica, Guatemala, Nicaragua, Panama, Peru.

Biology
Dijkstra and Boomsma (2006) investigated the viability of worker produced eggs in Atta cephalotes, Atta sexdens and Atta colombica. Most Atta workers have rudimentary, non-functional ovaries in a queenright colony but a few, typically tending the queen, can produce trophic eggs (Dijkstra et al., 2005). These eggs are feed to the queen. It was not known if any worker eggs can produce males. Most worker eggs of A. colombica did not contain yolk but a few did and yielded morphologically correct but very small males. They hypothesize that worker reproduction in orphaned Atta field colonies is almost never successful because the last workers die before their sons can be raised to adulthood, but the importance of worker-laid trophic eggs for queen feeding has precluded the evolutionary loss of worker ovaries.

Foraging
Bochynek et al. (2017) studied foraging rhythms in a colony of A. colombica in Panama: Foraging on the control (leaf) trail was diurnal and occurred in discrete periods approximately 10 h long. Activity began at dawn, rose to a peak in early afternoon and declined toward evening, with no foraging at night, a typical pattern for Atta leaf foraging (Lewis et al., 1974a). Leaf foraging on the berry/leaf trail followed a similar pattern. The peak harvesting rates, about 100–150 laden ant returns per min., were similar to the mean rate of 108 laden returns per min. observed by Bruce and Burd (2012) for colonies of A. colombica and Atta cephalotes in Panama and Costa Rica. Thus, leaf foraging was typical of colonies at other times and places.

Fruit foraging was fundamentally different. Harvesting was continuous with no periods of inactivity. There was, nonetheless, a diel rhythm. Throughout most of a 24 h cycle, fruit carriers returned at approximately the same rate as leaf harvesters at peak activity, but activity slowed to about 50 returns per min. in early morning, at 07.00 hours, before returning to a plateau of about 100–150 returns per min. for the remainder of the cycle.

Nomenclature

 *  colombica. Atta colombica Guérin-Méneville, 1844a: 422 (w.) COLOMBIA. Forel, 1913l: 239 (m.); Borgmeier, 1959b: 348 (q.); Wheeler, G.C. 1949: 681 (l.). Subspecies of lebasii: Emery, 1890b: 55; of cephalotes: Emery, 1913bb: 258. Revived status as species: Forel, 1913l: 239; Emery, 1924d: 353. See also: Gonçalves, 1942: 346; Borgmeier, 1959b: 345. Senior synonym of lebasii: Dalla Torre, 1893: 152; of erecta, tonsipes: Borgmeier, 1959b: 346.
 * lebasii. Atta lebasii Guérin-Méneville, 1844a: 422 (w.) COLOMBIA. Emery, 1890b: 54 (q.m.). Junior synonym of colombica: Dalla Torre, 1893: 152.
 * erecta. Atta cephalotes var. erecta Santschi, 1929f: 92 (diagnosis in key) (w.) COSTA RICA. Subspecies of cephalotes: Gonçalves, 1942: 345. Junior synonym of colombica: Borgmeier, 1959b: 346.
 * tonsipes. Atta columbica var. tonsipes Santschi, 1929f: 92 (diagnosis in key) (w.) PANAMA. Subspecies of colombica: Gonçalves, 1942: 346. Junior synonym of colombica: Borgmeier, 1959b: 346.