Adelomyrmex robustus

Adelomyrmex robustus

Adelomyrmex robustus is a small, dark ant from the cloud forests of southern Mexico and Guatemala. Workers measure about 3.6 to 3.8 mm long with black bodies, dark brown legs, and yellowish feet ^[1][2]. Their heads and bodies show a distinctive rough texture created by irregular ridges mixed with small pits, and they have two small pointed spines on their back ^[1]. This species lives in mature cloud forests between 1600 and 1900 meters elevation, where they can be incredibly abundant, showing up in over 90% of leaf litter samples in some areas ^[3]. Unlike many ants that claim exclusive territory, A. robustus often shares space with other species, including nesting alongside Adelomyrmex paratristani in the same dead plant galls and living near Perissomyrmex snyderi in rotting wood ^[3].

Quick Summary

• Difficulty: Expert
• Origin & Habitat: Southern Mexico and Guatemala, specifically mature cloud forest habitats at 1600-1900 m elevation ^[3].
• Colony Type: Unconfirmed, no studies have documented queen number or colony structure.
• Size & Growth:
  • Queen: ~4.1 mm total length ^[1][2].
  • Worker: ~3.6-3.8 mm total length (HW 0.83-0.88 mm) ^[1][2].
  • Colony: Unknown, not documented in research.
  • Growth: Likely slow, inferred from cool cloud forest habitat and small body size.
  • Development: Unknown, likely 8-12 weeks based on related myrmicine ants at cool temperatures, but unconfirmed. (Development time has not been studied. Cool cloud forest temperatures likely slow growth compared to tropical lowland species.)
• Antkeeping:
  • Temperature: Cool and stable, approximately 18-22°C (inferred from 1600-1900m cloud forest habitat). Avoid temperatures above 25°C.
  • Humidity: High humidity 70-80%. Keep nest material damp but not waterlogged, think cloud forest floor conditions.
  • Diapause: Unknown, likely not required for this tropical cloud forest species, but a cool resting period at 15-18°C may be beneficial.
  • Nesting: Pre-made cavities in dead wood or rotting wood. Naturalistic setups with wood or plaster nests with small chambers work best.
• Behavior: Cryptic and ground-dwelling. Frequently found at baits in the wild ^[3]. Small size means excellent escape prevention is essential.
• Common Issues: escape risk is high, at only 3.6mm long, workers squeeze through the tiniest gaps in mesh and lids., heat stress from keeping them too warm, cloud forest species suffer above 25°C., unknown founding behavior makes captive rearing risky, no studies confirm if queens found colonies alone or in groups., mold growth in high humidity setups without adequate ventilation.

Cloud Forest Habitat and Temperature

Adelomyrmex robustus comes from cool, wet cloud forests at 1600-1900 meters elevation in Chiapas, Mexico and Guatemala ^[3]. You will need to replicate these cool, stable conditions in captivity. Aim for 18-22°C with minimal fluctuations. Temperatures above 25°C likely cause stress, and prolonged heat can kill cloud forest specialists. Use a heating cable on one side of the nest to create a gentle gradient, but keep the overall setup cooler than typical tropical ants. If your room temperature exceeds 22°C, you may need to cool the nest with fans or place it in a cooler part of your home.

Nesting in Wood Cavities

In nature, these ants nest in dead wood, dead plant galls, and rotting logs ^[3]. They do not dig extensive soil tunnels. Instead, they move into pre-made cavities, often sharing space with other ant species like Adelomyrmex paratristani in the same dead gall ^[3]. Their brood is spread across multiple chambers rather than concentrated in one spot. For captive care, use a naturalistic setup with rotting wood or a plaster/formicarium nest with small, tight chambers. Avoid tall, open spaces, they prefer confined cavities similar to those found in decaying wood.

Feeding and Diet

These ants are frequent visitors to baits on the forest floor ^[3], suggesting they are generalist foragers. Offer small protein sources like fruit flies, springtails, or tiny pieces of mealworms. Provide sugar sources such as honey water or sugar water. Because they are small, cut prey into appropriately tiny pieces. Remove uneaten protein within 24 hours to prevent mold in their humid environment.

Colony Founding

Founding behavior is unconfirmed. No research documents whether queens found colonies alone (claustral) or need to forage (semi-claustral). Based on typical Adelomyrmex patterns, they likely found claustrally (sealed in), but this is speculation. If you obtain a queen, house her in a test tube with damp cotton and observe. Do not disturb her frequently. Success rates are unknown, so start with multiple queens if possible to increase your chances.

Escape Prevention

At 3.6-3.8 mm long, workers are tiny enough to squeeze through standard mesh and loose-fitting lids ^[1]. You must use excellent escape prevention. Use fine stainless steel mesh (under 0.5mm holes) for ventilation. Apply Fluon or PTFE barrier to the upper walls of outworlds. Check all connections and lids for gaps, if you can see light through a crack, they can likely squeeze through it.

Frequently Asked Questions

References