Pheidole morrisii
Morris's Big-Headed Ant
Photo: Connor Cashman, via iNaturalist, licensed under CC BY 4.0.
🐜 At a glance
Origin: Eastern USA; new York to Florida and Texas; sandy soil
Nest temperature: 24–28°C; best about 26°C; heater at 26°C
Outworld temperature: 18°C night, up to 28°C day; by day like the nest or a degree or two cooler
Humidity: Nest 50–70%; outworld about 50%, never watered
Winter: Natural rest (northern colonies); 10–15°C only in a hibernation unit, or room temperature
Move to a nest: 50+ workers; A queen on her own too (tiny workers)
Size: Queen 8–10 mm; minors 3–3.5 mm, majors 4–5 mm, yellow
Colony: Usually one queen; 5,000–10,000 ants when mature
📖 About this species
A fast-growing, golden-yellow big-headed ant from the sandy pine barrens and grasslands of the eastern USA. A North American ant, not sold by Best Ants UK and possibly illegal or impossible to import to the UK.
🍯 Feeding
Proteins: Protein Jelly (keep in the fridge) or Cricket Mash. Live food only for established colonies: scalded, cut in half, never smaller, no mealworms
Carbohydrates: organic Ant Honey or Ant Nectar, far better than sugar water or home-made mixes; small drops
Seeds: optional; keepers report captive colonies rarely take them. On tin foil only, never on the substrate
Twice a week, small amounts, outworld only; leftovers out after 2 days. Founding queen: a tiny drop of protein jelly on tin foil once a week
💧 Watering the nest
Distilled or purified water only. Never tap, rain or bottled mineral water, even boiled (mould and fungus).
Pipette a few drops through the watering hole; stop when 1–2 drops appear inside. About once a week, or when the meter drops below 50%.
Never water the outworld; keep it at about 50% humidity. A watering test tube in the outworld gives a safe drink.
🏠 Setting up the ant farm
A7 Plus ant farm kit only (small nest, built-in digital meter); Nest + Outworld option if you already have your ants
Advanced Heating System Small 4W under one quarter of the nest, opposite the watering area, set to 26°C
Daylight, never direct sunlight; away from windows, radiators, vibrations, speakers and kitchens
Escape risk: high, tiny fast workers. PTFE Fluon band on the top inner edge of the outworld lid, reapplied every 2–4 weeks
💡 Good to know
North American ant: not sold by Best Ants UK, and possibly illegal or impossible to import to the UK. We never encourage importing ants
Protein drives its fast growth; keep the outworld clean, as old scraps bring mould and mites. No rest in a queen's first year
Never release it. Can't keep it? See our ant adoption page
⭐ Golden rules | Never break these
🚫 Never put ants in a fridge, shed or garage, and never expose them to abrupt temperature changes.
🚫 Never use gel ant farms, Ytong or concrete nests, or DIY nests.
🚫 Never use tap, rain or mineral water, even boiled.
🚫 Never move a colony into a nest too early, and never tip or shake ants out of their tube.
🚫 Never release ants into the wild. If you can no longer keep a colony, visit our ants adoption page and ask us whether we can adopt it.
🛒 Recommended for this species
📚 These care notes cover the essentials only. Please read the full ant farm setup guide and our Pheidole morrisii care guide from A to Z. Questions? Message us through our contact form and we will be happy to help. 💚
Written and reviewed by the Best Ants UK team, keeping ants since 1997.