Agraulomyrmex wilsoni

Agraulomyrmex wilsoni

These are among the tiniest ants in African grasslands, with workers measuring just 1.5-1.9mm and queens only 3.6mm ^[1]. They are brown in color with pale legs and antennae, and have unusually large eyes for such small ants ^[1]. The type collection from Zimbabwe contained repletes (storage workers with swollen abdomens), suggesting they store liquid food ^[1]. Virtually nothing else is known about their biology, they have only been collected a handful of times in Zimbabwe and South Africa, mostly through pitfall traps in grassland habitats ^[1][2].

Quick Summary

• Difficulty: Expert
• Origin & Habitat: Zimbabwe and South Africa, collected in grassland pitfall traps ^[1][2].
• Colony Type: Unknown, colony structure has never been observed.
• Size & Growth:
  • Queen: 3.6 mm ^[1]
  • Worker: 1.5-1.9 mm ^[1]
  • Colony: Unknown, no wild colony has ever been studied.
  • Growth: Unknown
  • Development: Unknown, no data exists on development time. (Development time is completely unstudied. Based on their tiny size and Formicinae subfamily placement, development might be relatively fast (4-8 weeks) at warm temperatures, but this is pure speculation.)
• Antkeeping:
  • Temperature: Unknown, start at 22-25°C and observe activity levels. Adjust based on whether workers cluster near heat sources or avoid them.
  • Humidity: Unknown, grassland pitfall trap data suggests moderate humidity. Start with substrate that is lightly moist but not wet, with a gradient from damp to slightly dry.
  • Diapause: Unknown, collection data does not indicate seasonal activity patterns.
  • Nesting: Unknown, likely nest in soil or grassland litter based on collection method. A naturalistic setup with soil and grassland debris would be most appropriate, though unproven.
• Behavior: Temperament is unknown. Their extremely small size (1.5mm) makes escape prevention absolutely critical, they can pass through gaps that would stop larger ants ^[1].
• Common Issues: no established care protocols exist, you would be the first to attempt keeping this species., extreme escape risk due to 1.5mm worker size, standard barriers may not work., desiccation risk, tiny ants lose water rapidly if humidity drops., unknown dietary requirements, repletes suggest honeydew dependence but protein needs are unstudied., founding behavior is completely unknown, queens may fail without specific conditions we cannot predict.

Identification and Taxonomy

Agraulomyrmex wilsoni belongs to the tribe Plagiolepidini within the subfamily Formicinae ^[1]. Workers are immediately recognizable by their extremely small size (1.5-1.9mm), ten-segmented antennae without a distinct club, and large eyes that take up about one-fourth of the head length ^[1][2]. They closely resemble workers of the genus Acropyga but are smaller, darker, and have much larger eyes ^[1]. The mandibles have four sharp teeth, and the petiole (waist) has a very reduced scale that is almost invisible from above ^[1]. Queens are larger at 3.6mm but share the same general body plan ^[1].

Natural History

Almost nothing is known about how these ants live in the wild. The type series came from Gwebi, Zimbabwe, collected in December 1972 ^[1]. Additional specimens have been collected in South Africa from a grassland pitfall trap in the Pretoria Botanical Garden ^[1]. The presence of repletes (workers with distended abdomens used for food storage) in the type collection suggests they collect and store liquid carbohydrates, likely honeydew from sap-sucking insects ^[1]. This feeding strategy is common in their tribe, Plagiolepidini. The pitfall trap collection method indicates they forage on or near the ground in grassland habitats, but nest architecture remains completely unknown.

Housing and Escape Prevention

At 1.5mm long, these workers can squeeze through incredibly small gaps. Standard test tube setups may not be secure enough without additional barriers. If attempting to house them, you would need extremely fine mesh (much finer than standard fly screen) or complete enclosure within a sealed container. Fluon or other barrier products must be applied perfectly with no gaps. Even tiny imperfections in acrylic nests or between glass panes could allow escape. Given their unknown nesting preferences, a naturalistic setup with soil, small stones, and grassland plant material would be the most logical starting point, though this has never been attempted. ^[1]

Feeding

Diet is unknown, but the presence of repletes strongly suggests these ants are honeydew collectors ^[1]. In captivity, they might accept sugar water or honeydew substitute, but protein requirements are a complete mystery. They may require tiny prey items appropriate to their 1.5mm size, such as springtails or mite-sized prey, or they may rely primarily on liquid carbohydrates. Without knowing their natural diet, feeding would require careful experimentation starting with very small amounts to avoid mold or drowning.

Colony Founding

Founding behavior has never been observed. As members of Formicinae, they are likely claustral (queens seal themselves in and raise first workers on stored fat reserves), but this is unconfirmed. Queens might require specific humidity, temperature, or substrate conditions that are impossible to predict. They might also be semi-claustral (requiring food during founding) or even socially parasitic, though no evidence supports parasitism. Anyone attempting to found a colony would be working completely blind regarding queen care. ^[1]

Frequently Asked Questions

References