Bothroponera berthoudi

Bothroponera berthoudi

Bothroponera berthoudi is a large, dark African ant belonging to the Ponerinae subfamily. Workers measure 9.60-12.00 mm in total length and have a distinctive appearance with a black body, brownish-black legs and antennae, and reddish-brown mandibles ^[1]. The species is part of the Bothroponera pumicosa species complex and is found in southern Africa, particularly South Africa and Eswatini ^[1]. Unlike most ant species, B. berthoudi is queenless, reproduction is handled by gamergates, which are workers that have developed the ability to lay eggs ^[2]. This makes them fascinating for antkeepers interested in alternative social structures.

Quick Summary

• Difficulty: Medium
• Origin & Habitat: Southern Africa (South Africa, Eswatini), found in open habitats like savanna, thornveld, and farmland ^[3]
• Colony Type: Queenless, colonies are led by gamergates (reproductive workers). Multiple gamergates per colony, typically 1-46 individuals depending on colony size ^[2]. Polydomous colonies with 1-7 connected nests ^[2].
  • Colony: Polygyne
  • Special: Gamergates
• Size & Growth:
  • Queen: No queen, gamergates are reproductive workers ^[2]
  • Worker: 9.60-12.00 mm ^[1]
  • Colony: Average 91 workers in field colonies, range 20-207 ^[4]
  • Growth: Moderate, estimated 8-12 weeks from egg to worker based on Ponerinae patterns
  • Development: Estimated 8-12 weeks at 24-26°C based on related Ponerinae species (Development time is estimated as this species has not been directly studied. Virgin worker-laid eggs can develop but typically don't hatch in the presence of gamergates ^[4].)
• Antkeeping:
  • Temperature: Keep at 24-28°C, they originate from warm African habitats. A gentle heat gradient allows them to regulate temperature ^[3]
  • Humidity: Moderate humidity around 50-60%. They come from savanna and thornveld habitats which are not extremely wet. Provide a moisture gradient with a damp section and drier areas ^[3]
  • Diapause: No, as an African species from a warm climate, they do not require hibernation. Keep them at stable warm temperatures year-round ^[3]
  • Nesting: Polydomous nesting in nature, they use multiple connected nests. In captivity, provide a spacious formicarium with multiple chambers. Y-tong nests or naturalistic setups with soil work well. They prefer darker nesting areas ^[2]
• Behavior: These ants are predatory, primarily hunting termites and other small invertebrates ^[5]. They forage solitarily rather than in groups. Workers are moderately aggressive when defending the nest but are not particularly territorial. They have a functional stinger and can deliver a painful sting. Escape risk is moderate, they're large ants but not particularly agile climbers. Still, use standard barrier methods ^[2].
• Common Issues: queenless colonies can be confusing for beginners, there is no queen, only gamergates that reproduce, gamergate dynamics are complex, too many reproductive workers can reduce egg production efficiency, virgin workers may lay eggs but they typically don't hatch when gamergates are present, this can be mistaken for infertility, slow colony growth compared to queen-right species may frustrate some keepers, predatory diet means they need live prey regularly, they cannot survive on sugar alone

Understanding the Queenless Colony Structure

Bothroponera berthoudi is one of the fascinating queenless ant species, there is no queen in these colonies. Instead, reproduction is handled by gamergates, which are workers that have developed functional ovaries and can lay eggs ^[2]. This is a fundamentally different social structure from most ant species kept in captivity. In field colonies, gamergate numbers range from just 1 to as many as 46 individuals, making up 1-27% of the total worker population ^[2]. The proportion of gamergates varies based on colony conditions, in colonies with many gamergates, each individual has lower fecundity, while colonies with fewer gamergates have more fertile individuals ^[4]. This flexible system allows the colony to adjust reproductive output based on its size and resources.

Housing and Nest Setup

These ants need a spacious setup due to their polydomous nature in the wild, colonies maintain 1-7 connected nests ^[2]. In captivity, provide a formicarium with multiple chambers connected by tunnels. Y-tong (acrylic) nests work well, or you can use a naturalistic setup with soil and decorative elements. They prefer darker nesting areas and will often nest in the most shaded sections. Because they're large ants (9-12mm), they need appropriately sized chambers, too small and they'll feel cramped. Include a deep water reservoir in the outworld for drinking, and ensure the nest has good drainage to prevent flooding. A foraging area of at least 20x20cm is recommended for larger colonies.

Feeding and Diet

Bothroponera berthoudi is predatory, primarily hunting small prey like termites in the wild ^[5]. They forage solitarily rather than in groups, so you'll need to provide individual prey items. Their diet should consist mainly of live insects, termites, small crickets, fruit flies, and other small arthropods are ideal. They have a functional stinger and use it to subdue prey. While they may accept some sugar sources, protein-rich live prey is essential for colony growth and gamergate health. Feed prey items 2-3 times per week for established colonies, and ensure any uneaten prey is removed within 24 hours to prevent mold. A constant water source is also important.

Temperature and Humidity Requirements

As an African species from savanna and thornveld habitats, B. berthoudi needs warm conditions. Keep the nest area at 24-28°C, with a gentle gradient allowing workers to choose their preferred temperature. A heating cable or mat on one side of the nest can create this gradient, place it on top of the nest to warm the area without excessive drying. Humidity should be moderate, around 50-60% in the nest. These ants are not from extremely wet environments, so avoid overly damp conditions that could cause mold. Provide a water dish in the outworld for drinking. Unlike temperate species, they do not require any winter cooling period, maintain warm temperatures year-round. ^[3]

Colony Dynamics and Reproduction

The reproductive biology of this species is complex and differs from typical ants. Gamergates (reproductive workers) do most of their resting inside the nest and rarely venture outside ^[2]. When gamergate proportions are high (over 10% of the colony), they participate in colony tasks like brood care. When proportions are low, they rest most of the time and contribute little to labor ^[2]. Virgin workers can develop ovaries and lay eggs, but these eggs typically don't hatch when gamergates are present, this appears to be a regulatory mechanism ^[4]. If you want to try breeding them, separating virgin-laid eggs from gamergates by a double mesh barrier can allow them to develop. Males are active from January to March in the wild ^[2].

Handling and Temperament

These ants have a functional stinger and can deliver a painful sting if provoked. They are not aggressive toward humans when undisturbed, but will defend their nest if threatened. Workers are moderately large and relatively slow-moving compared to some ponerines. They are not particularly good climbers, so standard barrier methods like fluon on container rims should prevent escapes. When caring for them, avoid disturbing the nest frequently, they prefer stability and will thrive with minimal interference. Observe from a distance rather than handling directly. Their interesting behavioral repertoire includes the complex gamergate interactions and solitary foraging patterns that make them fascinating to watch. ^[2][5]

Frequently Asked Questions

References