How to Care for Myrmecocystus semirufus | The Half-Red Honeypot Ant Guide
Photo: Jake Nitta, via iNaturalist, licensed under CC BY 4.0.
Myrmecocystus semirufus is a bold, sun-loving honeypot ant from the desert mountains of California and Mexico. Its workers wear a rusty-red head and thorax over a dark back end, and some of them swell into golden living honey stores.
It is the half-red honeypot ant: a fast, busy daytime forager and a real hunter. This guide explains Myrmecocystus semirufus care step by step, from a founding queen to a colony with its own repletes.
Myrmecocystus semirufus is a North American ant, and Best Ants UK does not sell it. It may be illegal or impossible to import to the UK, and we don't encourage importing ants from abroad. This guide is for keepers where the species is native, and for anyone curious about it.
We have kept ants since 1997, and the care rules here are the same ones we use for our own colonies every day.
👉 In a hurry? Download our free Myrmecocystus semirufus care sheet (PDF) or open the Myrmecocystus semirufus care sheet page for the key facts at a glance.
Myrmecocystus semirufus at a Glance
Also known as: the half-red honeypot ant
Origin: desert mountain ranges of southern California and northern Baja California, Mexico
Keeping level: Intermediate
Queen: about 13 to 14mm, red head with a darker body
Workers: about 4 to 8mm, rusty-red head and thorax, dark gaster
Colony: one queen only, hundreds in the first year and 1,000 or more later
Nest temperature: 26 to 29°C
Nest humidity: 50 to 70%
Workers before moving into a nest: 10 minimum, 15 to 20 recommended
Winter: no rest in the first year; from the second year, a natural rest from November to the end of February
Escape risk: high, fast and active workers, so a PTFE barrier is a must
Meet the Half-Red Honeypot Ant
In the wild, Myrmecocystus semirufus lives on the slopes of desert mountains, among oaks, pinyon pine and juniper, sagebrush and creosote bush. It is found from central California south into northern Baja California.
The colony digs deep into firm, gritty ground, often at the edge of a dry stream bed. A low, wide crater of soil, up to about 25cm across, rings the entrance.
Unlike many honeypot ants, this one works by day and loves the sun. The workers are fast scavengers and skilled hunters, carrying home small dead insects such as leafhoppers, bugs, termites and flies.
In spring and autumn they also visit flowers for nectar. The sweet liquid is fed to the repletes, which swell into round golden stores and feed the colony through the dry months.
Each colony has a single queen, who seals herself away after her mating flight and raises her first workers alone. A healthy colony can live for many years.
When Your Ants Arrive
The most important step: leave the parcel completely unopened, exactly as it arrived, at room temperature for 5 hours. The ants must adjust to your home's temperature slowly, because abrupt temperature changes make ants seriously unwell.
After the 5 hours, check the queen is safe and sound. Then leave the colony in its original packaging, with the test tube still in its tin foil and wrapping.
Put it somewhere quiet and still, away from daily household activity. Normal daylight is fine, but never direct sunlight.
Give the colony 4 to 5 days of complete rest, with no food. A good supplier feeds the ants before dispatch. Use this time to set up and water the nest. 👉 Our step-by-step ant farm setup guide shows you exactly how.
Still workers or a motionless queen after delivery are almost always delivery stress. Look at the queen's antennae: moving antennae mean she is fine. Almost all recover within 4 to 5 days, and a big queen like this one can take a little longer.
Life in the Test Tube
Keep the colony in its test tube until it has at least 10 workers. 15 to 20 is even better. Moved earlier, the workers often abandon the queen in the bigger space, and the colony can fail. The same rule applies to a queen bought on her own.
A queen on her own still needs a little food. Once a week, give her a tiny drop of protein jelly, about half a grain of rice, on a small flat piece of tin foil inside the tube, next to the dry cotton stopper.
In our experience a fed queen raises her first workers faster, and the queen and colony do far better afterwards. Keep her tube wrapped in its foil, keep it warm and disturb her as little as possible.
With steady warmth, keepers find the brood takes about 7 to 9 weeks from egg to worker. A well-fed colony can reach a few hundred workers in its first year.
Moving Into the Ant Farm
When the colony is ready, connect the test tube to the nest with the delivery tin foil still on. Leave it like that for 14 days.
Then slide the foil back about 1mm every day until the tube is fully exposed to daylight. Bit by bit, the tube becomes the bright spot and the dark nest becomes the safe home.
If the ants haven't moved 2 days after the tube is fully exposed, wrap the foil back on, wait another fortnight and repeat. Moving in happens on the ants' own time: anywhere from a couple of days to 6 months.
Once the colony has moved, leave the old test tube connected for at least another 14 days, as ants sometimes leave brood behind.
The red filter and black cover stay on the nest all the time. You can lift the black cover once a day for 2 to 3 minutes, ideally at night, and take the red filter off once a week for 2 to 3 minutes. Take colony photos no more than once a month.
The Best Ant Farm for Myrmecocystus semirufus
Half-red honeypot ants are quick, curious foragers, so they need a well-sealed nest and a good-sized outworld to patrol in daylight.
👉 Our top pick is the A7 Plus ant farm kit. Its pre-installed digital meter shows nest temperature and humidity at a glance, which makes heating and watering far easier for a warmth-loving species like this.
Place the ant farm in normal daylight, never direct sunlight: even for a sun-loving ant, the sun can overheat a closed nest within minutes. Avoid windows, radiators and heaters, vibrating surfaces, speakers and TVs, and rooms with strong smells such as the kitchen.
Temperature and Heating
Keep the nest at 26 to 29°C. Warmth is what drives brood growth in honeypot ants, and a cool nest means a colony that barely grows.
Most UK homes are far cooler than that. 👉 The Advanced Heating System Small 4W holds a steady warm spot with its digital thermostat. Set it to 28°C.
The heat mat goes under one quarter of the nest only, on the side opposite the watering area. The ants can then move between the warm and cooler parts. Never heat the whole nest.
In the outworld, aim for about 18°C overnight up to 28°C by day. By day it should ideally match the nest or be a degree or two cooler. If the nest is heated, warm the outworld too, because a big gap confuses the ants.
Water and Humidity
This is a dry-country ant, so a soggy nest does far more harm than a slightly dry one. Keep the nest humidity at 50 to 70%. Use distilled or purified water only. Never use tap water, rainwater or bottled mineral water, even boiled: they cause mould and fungus.
Water the nest with the pipette provided. Pour slowly, a few drops at a time, through the watering hole. Stop as soon as 1 or 2 drops appear inside the nest. That is how you know it is done correctly.
Water about once a week, a little more in summer and a little less in winter. A heated nest dries out faster, so check the meter often and water when the nest humidity drops below 50%.
Never water the outworld. Keep it dry, at about 50% humidity, like an average UK home. A watering test tube in the outworld gives the workers a safe drink.
Feeding Your Honeypot Ants
Sugars matter more for honeypot ants than for almost any other ant, because the colony stores them in its repletes. Feed twice a week, in small amounts, in the outworld only. Remove leftovers after 2 days to stop mould.
🍯 For energy, give our 👉 organic ant honey or 👉 Ant Nectar, which has even more carbohydrates than honey. Offer it at every feed and never let them run short. Both are far better than sugar water or home-made mixes.
🥩 These are real hunters, and the brood needs plenty of protein. Give 👉 Protein Jelly or 👉 Cricket Mash. Keep protein jelly in the fridge at all times.
Serve food on a small piece of tin foil or in a 👉 small feeding dish, so leftovers are easy to lift out.
Live food, such as crickets or locusts, is only for big, established colonies, never small ones. Always scald it first: wearing gloves, hold it with tweezers in just-boiled water (above 90°C, no longer bubbling) for 10 to 15 seconds.
Then cut it in half only, and serve it in the outworld.
Keep Mites Out of Your Colony
Blood-sucking mites are one of the biggest dangers for any ant colony, and they are not rare. They often arrive with bird seed from local shops and off-licences, dried mealworms (useless as ant food), and live food from pet shops or online, where about half carries mites.
Buy ant food only from established, reputable ant-keeping suppliers. At Best Ants UK we clean our foods in several ways before dispatch and check every colony twice a month.
Live food always gets the scalding step above. Now and then, look at your queen with a magnifying glass. Tiny white or reddish specks on her joints and legs, together with ants dying fast, are a warning sign of blood-sucking mites.
Stopping Escapes
Half-red honeypot workers are fast, bold explorers, so escape prevention is a must. Paint a band of 👉 PTFE Fluon escape barrier around the top inner edge of the outworld lid. The ants slip off it and can't climb out.
PTFE wears off as the ants keep testing the same spots. For a small colony of up to about 100 ants, reapply it roughly every 4 weeks. For 300 to 500 ants or more, reapply it about every 2 weeks.
Never shake the bottle, because it foams. Roll it gently in your hands instead.
Winter Care
Best Ants UK never puts a queen into a winter rest in her first year. Keep the nest warm at 26 to 29°C all through her first winter.
From the second year, the colony has a natural winter rest from November to the end of February. In our experience this desert ant doesn't need a cold hibernation.
Simply switch the heater off and keep the colony at room temperature, around 20°C, for its rest. It slows down anyway, because its biological clock can't be tricked. Never put ants in a fridge, shed or garage, and avoid any abrupt temperature change.
Feed less in winter, but never guess. At 17 to 22°C, give about a third of the summer amount. At 22 to 26°C, give about half. Keep offering a little honey or Ant Nectar. In March, bring the nest back up to full warmth gradually.
Can I Release My Ants?
Never. Myrmecocystus semirufus is not a UK ant, and a colony raised indoors won't survive outside. If you can't keep your colony any more, 👉 visit our ant adoption page and let us know. We'll see whether we can take it in.
Frequently Asked Questions | FAQ
Is Myrmecocystus semirufus good for beginners?
It is an intermediate species. The colony needs steady warmth, plenty of sugars and a fresh PTFE barrier. For a very first colony, a beginner species such as Lasius niger is easier.
Can I buy Myrmecocystus semirufus in the UK?
Best Ants UK does not sell Myrmecocystus semirufus. It is a North American ant, and it may be illegal or impossible to import to the UK. We don't encourage importing ants from abroad.
Why is it called the half-red honeypot ant?
The workers have a rusty-red head, thorax and legs, while the back end (the gaster) is brown to almost black. Half red, half dark.
What temperature do Myrmecocystus semirufus need?
Keep the nest at 26 to 29°C. Most UK homes are much cooler, so an Advanced Heating System set to 28°C under one quarter of the nest is a must.
How many workers before moving Myrmecocystus semirufus into a nest?
At least 10 workers, and 15 to 20 is even better. Moved earlier, the workers often abandon the queen in the bigger space and the colony can fail.
Do Myrmecocystus semirufus hibernate?
Not in the first year. From the second year they have a natural winter rest from November to the end of February. They don't need a cold hibernation: switch the heater off and keep them at room temperature, around 20°C.
What do half-red honeypot ants eat?
Plenty of organic honey or Ant Nectar for energy, and Protein Jelly or Cricket Mash for the brood. In the wild they are keen hunters and scavengers of small insects. Feed twice a week, in the outworld only.
Ready for Your Own Honeypot Colony?
A thriving half-red honeypot colony can grow past 1,000 ants. When yours outgrows its first nest, 👉 the A6 ant farm kit with meter gives it more room, with a digital meter to keep heating and watering simple.
Print this guide and keep it next to your ant farm, so the essentials are always close. 👉 Explore all our free ant care sheets.
