Tetramorium simillimum

Quick Summary

• Difficulty: Expert
• Origin & Habitat: Native to tropical Africa, now pantropical across Africa, Asia, Australia, the Americas, and Pacific Islands. Also occurs in heated greenhouses in temperate Europe and North America ^[4][5]. Prefers disturbed areas, gardens, agricultural land, and urban environments ^[6].
• Colony Type: Polygynous, colonies typically have multiple queens working together ^[9]. Queens can coexist in the same nest. (Note: founding behavior is unconfirmed.)
• Size & Growth:
  • Queen: 2.3-2.6 mm ^[3]
  • Worker: 2.0-2.7 mm ^[1][2]
  • Colony: Up to several thousand workers in optimal conditions
  • Growth: Fast, these ants establish quickly
  • Development: Development timeline is not documented in available research. Based on typical Tetramorium patterns, egg to worker likely takes 6-8 weeks at warm temperatures, but this is unconfirmed. (Temperature depends, see requirements.)
• Antkeeping:
  • Temperature: Keep at 22-26°C for best growth. They tolerate a wide range but thrive with supplemental warmth. Critical thermal maximum is 42°C and peak activity occurs around 28°C ^[2]. Avoid letting them get below 18°C for extended periods.
  • Humidity: Moderate, keep the nest substrate slightly moist but not wet. A water tube provides adequate humidity. In dry artificial nests, add a small moist area. They prefer conditions that dry out gradually rather than staying constantly wet ^[4].
  • Diapause: Not required, as a tropical species, they remain active year-round when kept at room temperature. In unheated rooms they may slow in winter but do not need a cold period ^[5].
  • Nesting: Very flexible, they accept test tubes, Y-tong (AAC) nests, plaster nests, or naturalistic setups with soil. In the wild they nest in soil, under stones, and in rotting wood, so provide dark chambers and some substrate depth ^[6].
• Behavior: Workers are fast-moving, highly active foragers that use mass recruitment. They are diurnal with peak activity at dusk and during humid conditions ^[10]. They are omnivorous and will accept sugars and protein. They have a stinger but rarely use it, like other Crematogastrini, they smear venom rather than sting (general subfamily trait). Despite their small size they are bold but not aggressive toward humans. Escape prevention is critical because of their tiny size, use fine mesh and tight barriers.
• Common Issues: as an invasive species, never release colonies, extreme precautions needed to prevent escape, rapid colony growth can lead to overcrowding if the nest is too small, plan for expansion, tiny workers can squeeze through standard test tube plugs, use cotton or fine mesh, if kept in temperate regions, ensure stable warmth year-round since they don't hibernate, during founding, if multiple queens are kept together, monitor briefly for aggression (rare)

Housing and Nest Setup

Tetramorium simillimum is not picky about housing. Test tubes work well for starting colonies, keep the tube humid but not waterlogged. Once the colony outgrows the test tube, offer a Y-tong (AAC) nest, plaster nest, or naturalistic setup with soil substrate. They prefer dark chambers and a gradient from a humid nest area to a drier outworld. A standard water tube connected to the nest provides adequate humidity. Because these ants are tiny, make sure all connections are sealed with cotton or fine mesh to prevent escapes ^[11]. They will nest in soil, under stones, and in rotting wood in the wild, so providing some substrate depth is appreciated ^[6].

Feeding and Diet

These ants are omnivorous and accept a wide variety of foods. For sugars, offer honey water (diluted 1:4 with water) or sugar water regularly, they have a strong sweet tooth and will quickly recruit to these sources. For protein, offer small insects like fruit flies, pinhead crickets, and mealworms. In the wild, they tend hemipteran insects (aphids, scale insects) for honeydew ^[12], so they may also accept specialized ant foods containing honeydew. Feed every 2-3 days, removing any uneaten protein after 24 hours. Their small size means even tiny prey items are appreciated, flightless fruit flies are an excellent choice ^[13][6].

Temperature and Seasonal Care

Keep your colony at 22-26°C for optimal growth and activity. They can tolerate temperatures from roughly 18°C up to 30°C or higher, but growth slows at cooler temps. In their native tropical habitat and introduced ranges, they are active year-round, so no hibernation or diapause is required ^[2]. If you keep them in a room that gets cold in winter, consider using a heating cable or heat mat on one side of the formicarium. Their critical thermal maximum is 42°C, so avoid extreme heat ^[2]. They are highly adaptable and will do well in typical room temperature conditions in most homes.

Colony Structure and Multi-Queen Care

Tetramorium simillimum is polygynous, meaning colonies naturally have multiple queens. This makes them excellent for antkeepers who want quick growth, multiple foundresses can be kept together. However, because the founding method is unconfirmed, it is not certain whether queens seal themselves in or require feeding. If keeping multiple queens, provide multiple chambers in case of minor aggression. Once workers emerge, queen conflicts typically resolve. Colonies can grow quite large, potentially reaching several thousand workers in mature setups ^[4][9].

Behavior and Foraging

Workers are fast-moving and highly active foragers. They use chemical trails to recruit nestmates to food sources, forming visible trails within hours of discovering a food item. This mass recruitment allows them to quickly dominate baits, though they are not particularly aggressive toward other ant species. They are primarily diurnal but show peak activity during humid conditions and at dusk ^[10]. They are not dangerous to humans, their stinger is tiny and used mainly to smear venom (typical of Crematogastrini). Their small size means they can squeeze through tiny gaps, so excellent escape prevention is essential ^[6].

Frequently Asked Questions

Report an Issue

The current care sheet is based fully on literature. See inconsistencies, or something that's incorrect? Please report here, it will be resolved after review from an admin. Contributing to the blogs tab also helps providing information, to make us be able to further improve the caresheets. Thank you for your support!

References