Monomorium chilense 

Monogynous (single queen colonies are standard)

Up to 5,000–7,000 workers in mature colonies

Fast to Medium
(Growth is rapid in warm temperatures and with frequent protein feeding.)

• Queen: 5–6 mm

• Workers: 2–3 mm

Monomorium chilense workers are generally light to reddish brown, with a subtle sheen across the exoskeleton. Their small size and uniform coloration make them discreet but efficient foragers. Queens are slightly darker and more robust, with proportionally larger gasters.

• Insects: fruit flies, small mealworms, cut-up crickets

• Sugars: 3:1 or 4:1 sugar/honey to water syrup

• Fruits: apple, banana, pear (in small quantities)

• Protein sources: protein jelly, cooked unsalted egg white or chicken

• Supplement: tiny pieces of fish flakes or crushed dried insects

Tip: Due to their small size, offer finely chopped or soft-bodied food.

• Humidity:

  • Arena: 40–60%

  • Nest: 50–70%

• Temperature:

  • Arena: 24–30 °C

  • Nest: 23–27 °C

This species is adapted to dry and temperate climates and thrives with moderate warmth and humidity. Despite its tolerance for dry conditions, a lightly hydrated nest area is crucial for brood development.

• M. chilense is a tiny, agile species known for its highly efficient foraging and flexibility in diet.

• Colonies are non-aggressive and usually shy when disturbed, retreating rather than fighting.

• Due to their small size, they are excellent escape artists — tight-sealing setups are essential.

• Mini acrylic or 3D-printed nests with narrow chambers

• Test tube setups (ideal for founding stages)

• Plaster or YTONG nests with moisture gradient

• Avoid large open nests; they prefer compact, low-clearance environments.

Monomorium chilense is a small, fast-growing ant species suited for keepers who enjoy observing subtle behaviors and efficient colony dynamics. While visually modest, their adaptability, active foraging, and ease of care make them a great choice for both beginners and experienced keepers looking for a compact species. With proper humidity, secure housing, and consistent feeding, colonies will thrive and grow steadil