Fungal Symbiosis
There are many different species of fungus that grow alongside the domatia where the ants live. In fact, when the founding queen first starts laying eggs in the domatia of a new H. physophora, the hyphae of multiple different species of fungi will entirely cover the entrance to the domatia. When the worker ants mature, they actually have to dig their way through the fungal covering to get to the outside of the plant. However, almost even more remarkable, out of all of these fungal species, A. decemarticulatus will only cultivate one specific species. This fungus is a sooty mold which, according to one study by Mario X. Ruiz-Gonzalez et al. (2010), is characterized by closely related haplotypes (genetic markers) in the order Chaetothyriales. The ants use this mold to construct their traps.
Another noteworthy observation is that, unlike typical mutualisms between ant and fungus, these ants do not receive any nutrition from the fungus. They strictly manipulate the physiology of the fungus to construct a mortar for a trap that is able to catch much larger prey.
Read more about this topic: Allomerus Decemarticulatus