Workers are roughly 8–14 mm long; queens may reach about 20 mm.
Fine-art photographic collection
Cephalotes atratus
An armoured canopy ant that can steer through the air back to its tree.
About this species
Giant turtle ant
Cephalotes atratus(Linnaeus, 1758)
Information reviewed15 July 2026
Cephalotes atratus is a large arboreal turtle ant of tropical America. Colonies occupy cavities in living or dead trees, and workers forage across the canopy and trunk. When dislodged, they can control their fall and glide back toward a tree rather than dropping helplessly to the forest floor.
Taxonomy
Animalia · Arthropoda · Insecta · Hymenoptera · Formicidae · Myrmicinae · Cephalotini · Cephalotes
Accepted · checked 2026-07-15
Central and South American tropicsBroad documented localities — not a complete range map.
From Panama and northern South America south through Amazonia to Paraguay, Uruguay and northern Argentina.
Lowland tropical forest, woodland, parkland and urban trees, wherever suitable trunk or branch cavities are available.
Mainly diurnal. Workers use bark crevices and connected vegetation as routes through the canopy and may descend to forage on the ground.
Honeydew and other plant-associated liquids, pollen, carrion, bird droppings and small animal material.
Mature colonies may contain several thousand workers in a main tree cavity with occasional auxiliary nesting spaces.
What makes this species remarkable?
Experiments found that falling workers can steer abdomen-first toward a trunk and return to the canopy with very high success.
Workers can form an armoured living barrier at a nest entrance, placing their broad heads side by side against attackers.
A nematode parasite can turn the normally dark gaster red and berry-like, apparently increasing the chance that birds will eat it and spread the parasite.
More photographs
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