Bothroponera cariosa

Bothroponera cariosa - "Black Rugged Ringbum ant"

Bothroponera cariosa is a medium-sized African ant belonging to the pumicosa species complex. Workers measure 10-11.5mm with a distinctive black body and reddish-brown legs and antennae. The most identifying feature is the sharp longitudinal carina (ridge) on the clypeus (the area just above the mandibles). Their entire body is covered in short golden hairs, giving them a slightly fuzzy appearance. This species is found across southeastern Africa, including Mozambique, Tanzania, Eswatini, and parts of South Africa ^[1].

These ants are predators that specialize mainly on termites. They build nests underground or under stones in habitats characterized by high humidity and wet soils, think tropical rainforest floors and subtropical areas. Colonies remain relatively small compared to many other ant species. The combination of their striking black and reddish coloring, moderate size, and termite-hunting lifestyle makes them an interesting species for antkeepers seeking something beyond the common Lasius or Camponotus ^[1].

Quick Summary

• Difficulty: Medium
• Origin & Habitat: Southeastern Africa (Mozambique, Tanzania, Eswatini, South Africa). Found in rainforest and primary forest habitats with high humidity and wet soils ^[2][1].
• Colony Type: Likely monogyne (single queen) based on typical Bothroponera patterns. Colonies contain a small number of individuals ^[1].
  • Colony: Monogyne
  • Founding: Claustral
• Size & Growth:
  • Queen: Not documented, estimated 12-14mm based on genus patterns
  • Worker: 10.15-11.50mm ^[1]
  • Colony: Small colonies, likely under 100 workers based on 'small number of individuals' description ^[1]
  • Growth: Moderate, estimated based on Ponerinae development patterns
  • Development: Estimated 6-10 weeks at optimal temperature based on typical Ponerinae development (Development time is estimated, no direct studies exist for this species. Ponerine ants typically develop slower than Myrmicinae.)
• Antkeeping:
  • Temperature: Keep at 24-28°C. These are tropical/subtropical ants from humid forest habitats. A heating cable on one side of the nest creates a temperature gradient.
  • Humidity: High humidity is essential, they come from wet forest habitats with high soil moisture. Keep the nest substrate consistently moist but not waterlogged. Provide a water tube for drinking water ^[1].
  • Diapause: Likely minimal or no true diapause given their tropical/subtropical origin. However, they may reduce activity during cooler months. More research needed on seasonal behavior.
  • Nesting: In captivity, they do well in naturalistic setups with soil or in Y-tong/plaster nests. They naturally nest underground or under stones, so they prefer enclosed nest spaces with access to moist substrate. Avoid dry, arid setups.
• Behavior: Bothroponera cariosa is a predatory ant species that mainly hunts termites. They are likely moderate to good climbers but not particularly known for escaping. Workers are robust and can deliver a sting if threatened, this is a Ponerine ant, and many in this subfamily have functional stingers. They are likely more active during warmer months and may reduce foraging in cooler conditions. Their small colony size means you'll see fewer workers active at once compared to species like Lasius or Tetramorium ^[1].
• Common Issues: high humidity requirements can lead to mold if ventilation is poor, balance is key, small colony size means slower population growth, which can frustrate beginners expecting fast development, specialized termite diet may be difficult to replicate, need to offer appropriate protein sources, stinging capability means they can defend themselves, handle with care, limited availability in the antkeeping hobby means this species is rarely encountered

Housing and Nest Setup

Bothroponera cariosa does well in naturalistic setups that mimic their natural underground nesting habits. A formicarium with a soil chamber or a Y-tong/plaster nest works well. The key requirement is maintaining high humidity, these ants come from wet tropical and subtropical forests where the soil stays consistently moist. Use a substrate that holds moisture well, like a soil mix, and ensure there's always some water available, either through a water tube or by keeping one area of the nest damp. Avoid completely dry setups. Since colonies stay small, you don't need a massive outworld, a modest foraging area connected to the nest works fine. Provide some hiding spots and cover in the outworld since these ants may be somewhat shy. ^[1]

Feeding and Diet

In the wild, Bothroponera cariosa mainly feeds on termites ^[1]. In captivity, you'll need to replicate this protein-rich diet. Offer small live prey like mealworms, small crickets, and most importantly, termites if you can obtain them. Some keepers report success with other small insects as well. Since they're predators, protein should make up the majority of their diet. You can occasionally offer sugar water or honey as a supplement, but don't expect them to rely on sweets like some Formica or Lasius species do. Feed them every few days, removing any uneaten prey after 24 hours to prevent mold. A varied diet of different small insects helps ensure proper nutrition.

Temperature and Humidity

These ants require warm, humid conditions to thrive. Keep the nest area at 24-28°C, this is typical for tropical and subtropical species. A small heating cable placed on one side of the nest creates a temperature gradient that lets the ants choose their preferred spot. Humidity is critical: maintain consistently moist substrate without flooding. The natural habitat is characterized by high humidity and wet soils, so don't let the nest dry out. A water tube connected to the formicarium helps with both drinking water and maintaining humidity. Monitor for mold, which can be a problem in overly humid setups with poor ventilation. Strike a balance between keeping things damp and allowing some air flow. ^[1]

Behavior and Temperament

Bothroponera cariosa is a predatory ant with a moderate temperament. They're not typically aggressive toward keepers but can defend themselves if threatened. Like many Ponerine ants, they possess a functional stinger, so there's a potential for painful stings if you handle them roughly or disturb the nest. Workers are robust and moderately active, hunting individually for prey rather than forming large foraging trails. Colonies remain relatively small, so you won't see the massive worker activity you'd get from species like Lasius niger. They're likely more active during warmer months and may reduce activity when temperatures drop. Their hunting behavior is interesting to watch as workers search for termites and other small prey. ^[1]

Colony Development

Colony growth for Bothroponera cariosa is likely slower than many common hobby species. Based on typical Ponerinae development patterns, expect 6-10 weeks from egg to first worker at optimal temperature. Colonies remain small, likely maxing out around 50-100 workers in captivity. The queen lays eggs progressively, and the first workers (nanitics) are typically smaller than mature workers. Because colonies stay small, each worker is valuable, avoid disturbing the nest too much during founding and early growth. Patience is key with this species. A well-established colony with consistent feeding and proper conditions can grow steadily over several years.

Seasonal Care

Given their origin in tropical and subtropical Africa, Bothroponera cariosa likely doesn't require a true hibernation period. However, they may experience reduced activity during cooler months in their natural range. In captivity, you can maintain year-round warmth if you have heating. If your room temperature drops significantly in winter, consider using a small heat source to keep them in their optimal 24-28°C range. Don't be alarmed if activity slows somewhat during winter months, this is normal adjustment rather than true diapause. Continue offering food, just perhaps slightly less frequently if workers seem less interested. Avoid letting temperatures drop below 20°C for extended periods. ^[1]

Frequently Asked Questions

References