Common names: The Arboreal Bicolored Ant / The Asian Bullet Ant.
The workers of this species are about 10 - 12 mm and have a very slender body with short legs. The head, abdomen and top portion of their legs are black and their thorax/petiole are orange-red.
The queens are slightly larger than the workers at about 13 - 15 mm and easily distinguishable by their more robust thorax and larger gaster. In Northern Thailand, the alates are produced in January/February which is at the end of the cold season. The females and males are a similar size suggesting mating takes place on the ground or on nearby shrubs.
The new queens form colonies independently and can frequently be seen outside their foundation chamber foraging. Sometimes several queens will group together to establish a colony and they will stay together as the colony grows, to create a large multi queen colony. Colonies seem to vary in size from about 300 - 800 workers.
For the first year after a colony is established the queens are not given much attention and tend to act like normal workers, but once a colony is well established with a good force of workers the queens become more swollen, and the workers become much more attentive.
Established colonies can usually be found nesting in old dead hardwood which is extremely difficult to get into, and the entrance to their nest is often very small with just enough room for a worker to squeeze in, hence the colony is well protected from predators. In looking for a place to create a nest the new queens will utilize passages left by other insects such as wood borers, and then as her colony increases in size, they will slowly over time carve out larger chambers.
Their natural habitat is seasonal tropical forests where they create nests in old dead tree stumps, but they can also be found near human habitation where they will nest in posts and beams. Where no suitable wood is present, they will nest in the hollow stems of woody plants.
In captivity, they seem to take to most types of artificial nest, and if given a spoonful of earth they will produce a mud/saliva mix to reduce the size of the entrance so just a single worker can fit through – this action gives them a sense of security. Because of their natural instincts, they respond very well if kept in artificial nests which are carved out of wood.
This species is particularly adapted to an arboreal existence and is a very good climber. They prefer to forage over trees and large shrubs but can also be found foraging over the ground. They have large compound eyes and very good eyesight and will dart to the far side of twigs or branches when approached. It is mostly a day-active species that start to forage as the temperature rises in the morning.
They are very territorial against their own kind and workers will instantly attack any workers from other colonies. They are aggressive predators and in the wild feed on other ant’s alates, small insects, sugary excretions and termites.
They respond well to captivity but are best housed in a set-up that mimics their natural arboreal habitat, with plenty of branches to forage along. You should also remember that they are very good at climbing so their enclosure needs to have a good cover to prevent escapes.
The locals treat this species with great respect and do not disturb them as they have a very painful sting, which they will use at the slightest hint of threat. The stings effect is likened to a wasp sting and will often be followed by a painful swelling for several hours. Because of this, we are restricting sales of this species to customers over 18 years of age.
We prefer the common name used by the locals of ‘The Asian Bullet Ant’. You may also see Diacamma rugosum called by this name. Diacamma was given the name by an ant seller many years ago purely for commercial reasons because he wanted to promote sales of his stock. In our opinion the local name passed down over generations, and given because of the species extremely painful sting should take precedence.
Summary: This is an attractive species that respond well to captivity, they are attractively coloured and breed quick.
However, they should be treated with caution, because they are very good at escaping and can give a very painful sting.