Leaf-cutter ant

Description:

Atta sexdens, along with A. cephalotes, is the most widespread member of its genus. Its northern most range is Mexico, and extends through Central America (Panama, Costa Rica, Guatemala, Nicaragua), into South America (Ecuador, Columbia, Peru, Bolivia, Venezuela, Guyana, Brazil, Surinam) and Trinidad and Tobago (Hlldobler & Wilson, 1990; Kempf, 1972; Weber, 1972). The species has a wider tolerance for nest habitats, and is found in closed-canopy-forest, open grassland and disturbed habitats (Solomon, 2007; Weber, 1969). Atta sexdens is a considered a serious pest throughout its range, causing damage to a wide variety of agricultural crops and ornamentals (Cherrett, 1986). Atta sexdens is highly variable, both within the same colony and across populations. Workers vary in shape, color, sculpture and pubescence (Borgmeier, 1959). Among intercepted attines, the species is most readily confused with A. cephalotes, but can be distinguished by the lack of wooly hairs on the heads of major workers, the duller more opaque integument caused by a dense netting of hexagonal microsculpture, and the 1-2 small teeth or dents on the head anterior to the posterolateral spines. Among other attines, A. sexdens is most readily confused with A. capiguara, but can be separated by the microsculpture netting referred to above (Borgmeier, 1959).

Habitat:

The northern most range is Mexico, and extends through Central America (Panama, Costa Rica, Guatemala, Nicaragua), into South America (Ecuador, Columbia, Peru, Bolivia, Venezuela, Guyana, Brazil, Surinam) and Trinidad and Tobago.

Notes:

Leaf-cutter ants slice leaves, carry pieces back to the underground nest for further processing and, like tiny mushroom farmers, grow an edible fungus on the resulting substrate. The ants doing the cutting are usually members of the generalized forager caste, one of four size-based behavioral castes of workers. The foragers are second in size to the majors, the large workers that protect the colony and do heavy clearing work on the trails constructed to connect the nest to the leaf sources. In addition to cutting, the foragers transport the cuttings, scout for new resources and also help protect the colony.