The difference between Acro and Atta nest entrances

[Acromyrmexbob]

They are very different. Atta have a sophisticated way to divert water from the nest, building a lovely cone structure which disappears as they mature. Acromyrmex have a much more primitive arrangement, relying on the position of the fungus garden in relation to the entrance to avoid floods.


Atta cone


Acromyrmex octospinosus entrance.