Ectomomyrmex astutus

If you like predatory ants that move with intent rather than swarming, this Bornean species rewards close watching. Workers stalk their prey with a measured, deliberate gait that is easy to follow under the lid, and the dark, heavily built bodies look the part of a forest-floor hunter. Founding is semi-claustral, so the queen forages a little while raising her first brood, and growth stays slow and steady. The patience it asks for is exactly why it sits at Intermediate, and it suits keepers who value calm hunting behaviour.

A ponerine hunter that subdues prey individually rather than recruiting trails, the sighted foragers stinging and carrying live insects straight back to the brood. Workers also lap up sugars for their own energy, but it is the protein that keeps the larvae developing.

★★★ readily · ★★ moderately · ★ occasionally · ✗ not eaten

Found this Bornean predator in a test tube and leave it there until the first nanitics cover the floor, then shift it into a moisture-holding nest. Ytong or aerated concrete suits it best, since it wants damp walls and stable humidity near the brood. Pair the nest with a roomy hunting arena and seal the rim with fluon (PTFE), oil, or talc and water to stop wandering workers. ANTonTOP formicaria and starter kits bundle a damp nest, arena and barrier sized for this larger predatory genus.

This is a Bornean lowland ant, so warmth and damp air come first: hold the nest around 24-27 °C and the arena at 25-29 °C, with humidity high at 70-85% in the nest and 60-75% in the arena. Warm one zone a little more than the rest so workers can carry brood to the spot that suits it. Being tropical, it takes no winter rest and should be fed steadily through every month.

Expect a patient build. The colony climbs at a medium-to-slow pace toward a ceiling of about 500 workers, so the nest stays watchable rather than crowded and you can follow individual hunters with ease. Your colony arrives as a single queen with a cluster of workers and developing brood, ready to settle into a humid setup.

• Ectomomyrmex belongs to the Ponerinae, an ancient subfamily whose members hunt as individuals and keep a functional sting, closer to the ancestral ant way of life than the trail-laying species most keepers start with.
• Workers rely far less on sharing liquid food mouth-to-mouth than formicines do, so much of the colony’s nutrition comes straight from prey carried into the nest.
• The genus was long lumped into Pachycondyla, and many species were only split back out as Ectomomyrmex in recent taxonomic revisions, which is why older care notes still use the old name.
• These are cryptic, ground-dwelling ponerines that forage in leaf litter and rotten wood across Southeast Asia rather than out in the open.

Is the Bornean predatory ant Ectomomyrmex astutus good for beginners?

It is rated Intermediate; the slow development suits a keeper with some experience.

Does Ectomomyrmex astutus need a winter rest?

No. It is tropical and active year-round.

Does this Bornean ponerine sting or bite?

Yes, it has a sting, but the bite is mild.

How big does the colony get?

Up to 500 workers.

How large is the queen?

The queen is 12-13 mm; workers are 9-12 mm.

How fast does it grow?

At a medium-to-slow pace, gradual rather than rapid.

What does it eat?

Mainly insect prey, with sugar water or jelly for energy.

Will the ants arrive alive?

Colonies ship with a queen, workers, and brood plus a heat or cool pack, sent within 24 h with tracking for a safe, live arrival.

Escape prevention. Coat the inner rim of every open arena with fluon (PTFE), or use talc-and-water or an oil barrier as a backup, and keep a tight, fine-mesh lid on top. Check the barrier regularly, since dust, condensation and feeding debris break a fluon line over time. Keep tubing connectors tight and seal any gaps in the nest.

Keeping reminders. Always offer fresh water and never let the nest dry out completely. Give carbohydrates continuously and protein a few times a week, and remove uneaten insect prey within 24 hours before it moulds. Keep the formicarium out of direct sunlight and away from constant vibration, which stresses a young colony. A water-filled test tube plugged with cotton makes an ideal spare incubator whenever you need one.

Before you buy – do not rehouse too early. Have a test-tube setup or a small formicarium with an outworld and a working barrier ready before your colony arrives. A founding colony grows slowly at first, which is normal. Moving a small colony into a large nest too soon invites mould, mites and stress, and the workers die off one by one. Keep the colony in its open test tube on the arena, plug the nest entrance with cotton, and open up the next chambers only once the colony fills roughly 10-15% of the space.

What we ship. Every colony ships with a live-arrival guarantee, backed by our 24h unboxing-video guarantee: if the queen does not arrive alive, we reship free. Parcels travel with DHL, InPost (PL) or EMS, with a heat or cold pack to suit the season, packed discreetly and securely. We ship across the EU and worldwide, with free shipping over the Europe threshold.