Acromyrmex balzani

A leafcutter ant carries a grass stem back to her nest. Leafcutter species tend to specialize on either broadleaf plants or grasses. Entre Rios, Argentina

Acromyrmex coronatus

Cutting through a leaf. Laboratory colony at the University of Texas, collected from Panamá

Acromyrmex coronatus

A crowned leafcutter ant pauses on the Amazonian forest floor. Peru.

Acromyrmex coronatus

Leafcutter ants slice characteristic circular patterns in vegetation. Laboratory colony at the University of Texas, collected from Panamá.

Acromyrmex coronatus

Leafcutter ants slice characteristic circular patterns in vegetation. Panamá.

Acromyrmex crassispinus

Curitiba, Paraná, Brazil

Acromyrmex crassispinus

A leafcutter ant worker carrying a live aphodiine dung beetle, for reasons we can only guess. It is possible, for example, that the beetles breed in the ant's midden chambers, helping the ants to process waste, and the adults are attractive to the ants as a way of locating a suitable nest. Curitiba, Paraná, Brazil

Acromyrmex sp. nr. crassispinus

Acromyrmex sp. nr. crassispinus cutting into an orange peel. Citrus is a favorite target for leafcutters, perhaps because the plants are not native to the Americas and have not yet evolved defenses against the voracious ants. Lagunas de Yala, Jujuy, Argentina

Acromyrmex sp. nr. crassispinus

Up close with a leafcutter ant showing her impressive slicing mandibles. Lagunas de Yala, Jujuy, Argentina

Acromyrmex disciger

In a remnant of Brazil's once-great Atlantic coastal rainforest, an Acromyrmex disciger leafcutter ant carries a leaf back to her nest. The forest where these ants live has been 95% destroyed by human activities. Morretes, Paraná, Brazil

Acromyrmex disciger

When both Acromyrmex disciger leafcutting ants and Pheidole vafra big-headed ants arrive at a cookie bait I placed on the ground, fighting ensues. Although the Pheidole won this particular fight, the larger battle went to the leafcutters, and within 20 minutes of taking this photo the Pheidole had vanished. Morretes, Paraná, Brazil

Acromyrmex echinatior

An Acromyrmex echinatior leafcutter worker displays a microbial white patch on her underside made of Actinomyces bacteria. The bacteria are thought to produce antibiotics protecting the ants' fungus garden from infection- a true example of pesticide use among agricultural insects. Panama; Laboratory colony at the University of Wisconsin at Madison

Acromyrmex echinatior

A leafcutter worker with Actinomyces bacteria on its chest. The bacteria are thought to produce antibiotics protecting the ants' fungus garden from infection. Panama; Laboratory colony at the University of Wisconsin at Madison

Acromyrmex echinatior

Inside the spongy galleries of the fungus garden, Acromyrmex echinatior leafcutter workers display microbial white patches on their chests made of Actinomyces bacteria. The bacteria are thought to produce antibiotics protecting the ants' fungus garden from infection- a true example of pesticide use among agricultural insects. Panama; Laboratory colony at the University of Wisconsin at Madison

Acromyrmex echinatior

Panama; Laboratory Colony at the University of Wisconsin at Madison

Acromyrmex echinatior

Panama; Laboratory colony at the University of Wisconsin at Madison

Acromyrmex sp. cf. hispidus cuts an orange peel. Laboratory colony at the University of Wisconsin

Acromyrmex lobicornis

Amaicha del Valle, Tucumán, Argentina

Acromyrmex lobicornis

Amaicha del Valle, Tucumán, Argentina

Acromyrmex lundii

A leafcutter ant finishes a cut. Correa, Santa Fe, Argentina.

Acromyrmex lundii

Correa, Santa Fe, Argentina

Acromyrmex niger

A leafcutter ant worker makes a characteristically circular cut in a citrus leaf. Monte Verde, Minas Gerais, Brazil