However, some members show considerable evolutionary advancement in behaviors such as slave-making and symbiosis with root-feeding hemipterans.

[citation needed] All members of the Formicinae "have a one-segmented petiole in the form of a vertical scale".

[2] Formicine ants have a single node-like or scale-like petiole (postpetiole entirely lacking) and the apex of the abdomen has a circular or U-shaped opening (the acidopore), usually fringed with hairs.

A functional sting is absent, and defense is provided by the ejection of formic acid through the acidopore.

If the acidopore is concealed by the pygidium and difficult to discern, then the antennal sockets are located well behind the posterior margin of the clypeus (cf.