Odontomachus rixosus

Compact but every bit a predator, this Borneo trap-jaw runs the same spring-loaded weapon as its larger relatives: mandibles latched open under tension and fired shut to catch prey or to fling the ant clear of a threat. It comes from steamy rainforest with no cool season, so it stays busy all year, and being polygyne it can lift its worker count with more than one laying queen. The colony stays display-sized rather than overwhelming. The constant heat, high humidity and live-feeding routine put it in Pro territory, suited to keepers comfortable with demanding tropical setups.

A live-prey hunter that hunts by sight and fires its sprung jaws shut the instant a target touches its trigger hairs. Insects drive brood growth, with sugary liquids fuelling the workers themselves.

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

Start in a test tube and upgrade once founding workers cover the floor and brood builds. From hot, wet Borneo forest, this trap-jaw needs a moisture-holding nest in Ytong, gypsum or a hydratable hybrid kept consistently damp on the warm side. Set it next to a generous arena so the colony has room to hunt. The workers are quick and will climb, so seal the setup and run a fluon (PTFE) barrier, or oil where PTFE will not adhere. ANTonTOP formicaria and starter kits cover this colony from founding to its first few hundred workers.

Borneo means hot and wet with no real seasons, so feed that into the setup: nest at 24-27 °C and arena pushed to 25-29 °C. Hold nest humidity high at 75-90% and the arena at 65-80%. Heat one end only so the colony can settle along a warm-to-cool gradient. There is no cooling period: feed normally year-round and never let the temperature dip.

This colony builds at a moderate, consistent rate toward around 300 workers, with the polygyne multi-queen setup helping numbers along. Plan housing upgrades as the brood stacks grow. You receive a queen, or queens, with workers and brood, ready for a warm, humid home.

• The trap-jaw mechanism behind this ant ranks among the fastest self-powered movements known in the animal world.
• A worker can slam its mandibles into the ground and launch itself backwards, an escape jump driven by the same spring it uses to feed.
• Touched trigger hairs inside the gaping jaws set off a reflex among the quickest recorded for any animal.
• Unlike most ants, trap-jaws rely heavily on eyesight to track and catch moving prey.

Is this a good beginner ant?

No. It is Pro-rated and best for keepers used to hot, humid, live-prey setups.

Does Odontomachus rixosus need a winter rest?

No, this is a tropical species with no hibernation; keep it warm and active all year.

Does this trap-jaw sting or bite?

Yes, its sting is painful, so keep hands out of the arena and work carefully.

How big can the colony get?

Up to around 300 workers, helped by the polygyne multi-queen structure.

How large is the queen?

Queens are 11-13 mm and workers 10-12 mm.

How quickly does the colony build?

Moderately and steadily rather than in sudden bursts.

What do trap-jaw ants feed on?

Live and freshly killed insects plus sugar water, nectar or jelly for energy.

How is it shipped?

As a queen with workers and brood, packed with a heat or cool pack and sent within 24 hours with tracking for 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.