Formica sanguinea

This blood-red wood ant from France is famous for its forceful, opportunistic behaviour, raiding the nests of other Formica to take their brood, which makes it one of the more dramatic species in the hobby. Its queens can live up to around 20 years, so a strong colony stays with you for the long haul. It defends itself with formic acid rather than a sting, a classic Formica trait that is fascinating to watch safely. Rated Intermediate, it suits a keeper ready for a warm gradient, a long-term commitment, and a more deliberate growth curve.

An omnivore that captures insects to feed the brood and takes honeydew from aphids to power the workers. Keep a sugar source available at all times and offer protein two to three times a week.

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

Found this confident slave-making ant in a test tube or small starter nest, then upgrade to an aerated concrete or acrylic nest once the founding chamber is full. Run the nest fairly dry with a single damp brood area, matching its warm, drier preference. It is an active, bold forager, so keep the arena escape-proof with a fluon (PTFE) or oil barrier, or talc and water if you like. ANTonTOP formicaria and starter kits carry the colony from founding tube through to a settled nest, with the arena and barrier included.

Run it warm and fairly dry: nest at 20-25 °C, arena at 22-28 °C, with humidity at 50-65% in the nest and 35-55% in the arena. Warm one end to create a gradient the colony can move along. Wintering is mandatory for this northern-ranging ant, a cool rest at 5-10 °C for 4-5 months that keeps its yearly cycle healthy.

Growth is on the measured side here, with brood taking around 10 weeks to develop, and a mature colony settles at up to 5,000 workers. A strong colony is a long commitment, with a queen that can head it for many years. You receive the queen with workers and brood, ready to establish in a warm nest.

• Formica sanguinea is the best-known facultative slave-maker among ants: workers raid the nests of other Formica, carry off the pupae, and raise the emerging workers as part of their own colony.
• Because the raiding is facultative, a colony can also get by without captured workers, which makes it a favourite subject for studies of how slave-making evolves.
• A new queen often founds by invading a host colony and taking over, rather than starting entirely alone.
• Like all Formica it has no sting and defends itself by spraying formic acid, here from a notably bold and aggressive workforce.

Is Formica sanguinea good for beginners?

It is Intermediate, suited to keepers who can manage a warm gradient and a slower-building colony.

Does it need hibernation?

Yes, a winter rest at 5-10 °C for 4-5 months is mandatory.

Does it sting?

No. It has no sting and defends itself with formic acid instead.

How big does the colony get?

Up to 5,000 workers in a mature colony.

How large is the queen?

The queen is 9-12 mm; workers are 6-9 mm.

How fast does it grow?

Brood takes about 10 weeks, so growth is steady rather than fast.

What does it eat?

Sugar water and nectar or jelly for energy plus insects like crickets and flies for protein.

Will it arrive alive?

Yes, the queen ships with workers and brood and a heat or cool pack within 24 h with tracking.

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.