Back of Beyond The NT: November 2011

In Batesian mimicry in insects, an edible insect looks similar to an aposematic, inedible insect. The inedible insect is called the model, and the lookalike species is called the mimic. Hungry predators that have tried to eat the unpalatable model species learn to associate its colors and markings with an unpleasant dining experience. The predator will generally avoid wasting time and energy catching such a noxious meal again. Because the mimic resembles the model, it benefits from the predator's bad experience.

Ant mimicry is mimicry of ants by other organisms. Ants are abundant all over the world, and insect predators that rely on vision to identify their prey such as birds and wasps normally avoid them, either because they are unpalatable, or aggressive. Therefore, some insects mimic ants to escape predation (protective mimicry).

Green Ants Oecophylla smaragdina are very numerous in the top end of the Northern Territory. Green Ants prey on small insects and supplement their diet with carbohydrate-rich honeydew excreted by small insects (Hemiptera). These ants are highly territorial and workers aggressively defend their territories against intruders. Because of their aggressive behaviour, Green Ants are sometime used by indigenous farmers, particularly in southeast Asia, as natural biocontrol agents against agricultural pests.

Therefore it would be advantageous for an insect to mimic a Green Ant for defence against preditors who avoid Green Ants, as well as, as a defence against Green Ants themselves.

In this case, the pod-sucking bug Riptortis serripes (while an instar and lacking wings to escape) mimics the Green Ant Oecophylla smaragdina.

Green Ant Oecophylla smaragdina With Elateroid Beetle Porrostoma sp