Strumigenys undras

Quick Summary

• Difficulty: Expert
• Origin & Habitat: Found in Indonesia (Aru Islands), New Guinea, and the Solomon Islands. Inhabits rainforest and humid forest leaf litter ^[1].
• Colony Type: Colony structure is unconfirmed. Based on related Strumigenys, colonies likely contain few queens (possibly monogyne).
• Size & Growth:
  • Queen: Queen size unknown, worker size is 2.1mm ^[1]
  • Worker: 2.1mm total length ^[1]
  • Colony: Unknown. Inferred from related Strumigenys to be small (likely under 100 workers).
  • Growth: Slow
  • Development: Unknown for this species. Based on related Strumigenys, expect several months at optimal temperature. (Development is likely slow given their small size and specialized biology.)
• Antkeeping:
  • Temperature: These tropical rainforest ants ^[1] need warm, stable conditions. Keep the colony at 22-26°C. Avoid fluctuations.
  • Humidity: High humidity is essential. Keep the nest substrate consistently moist but not waterlogged, mimicking a damp forest floor.
  • Diapause: Unlikely – being a tropical species, they probably do not require a diapause period.
  • Nesting: Use a naturalistic setup with moist substrate or a small test tube setup. They prefer tight, dark spaces, similar to their leaf litter habitat.
• Behavior: These ants are extremely small and cryptic. They are believed to be specialized predators that hunt tiny arthropods. Workers are not aggressive and will flee from disturbance. Escape prevention is critical due to their tiny size – they can slip through standard barriers. They are slow-moving and spend most of their time in dark, hidden spaces.
• Common Issues: escape prevention is critical due to their very small size – they can slip through standard barrier setups, specialized diet makes them difficult to feed – they likely need live springtails or very small prey, which can be hard to maintain, high humidity requirements can lead to mold problems if not managed, slow growth and small colony sizes mean colonies are fragile, wild-caught colonies may have parasites that are difficult to detect

Housing and Nest Setup

Strumigenys undras requires a setup that mimics its natural leaf litter habitat ^[1]. A small test tube setup works well for founding colonies, while established colonies do best in a naturalistic setup with moist substrate. Keep the nesting area dark – these ants are believed to be cryptobiotic (preferring hidden spaces). Use very small chambers and narrow passages scaled to their tiny 2.1mm size ^[1]. Escape prevention must be excellent: apply Fluon or use fine mesh barriers, as they can slip through tiny gaps. A small outworld for feeding is sufficient since they don't travel far.

Feeding and Diet

Strumigenys undras inhabits leaf litter ^[1] and, like other Strumigenys, is thought to be a specialized predator of live prey. Their likely primary food source is springtails (Collembola) – small arthropods found in leaf litter. Other potential prey includes very small insects, booklice (psocids), and other micro-arthropods. They are unlikely to accept sugar sources or dead prey. Feed small live prey every few days, adjusting based on colony consumption. If the colony is hunting actively, you will see workers carrying prey back to the nest.

Temperature and Humidity

These tropical rainforest ants ^[1] need warm, stable conditions. Keep the colony at 22-26°C. Avoid temperature fluctuations and cold drafts. High humidity is essential, maintain substrate that feels damp to the touch. Provide a moisture gradient so ants can choose their preferred humidity. Mist occasionally but avoid standing water. Good ventilation is important to prevent mold while maintaining humidity. A small water reservoir in the nest helps stabilize humidity.

Behavior and Colony Dynamics

Strumigenys ^[1] are generally slow, deliberate foragers that hunt by stalking and capturing small prey. Workers are not aggressive and will retreat when threatened. Colonies are small and grow slowly – do not expect rapid expansion. Queens are likely claustral (seal themselves in to raise first workers) based on genus patterns, though this is unconfirmed for this specific species. Workers likely have short lifespans, so colony maintenance requires patience. Watch for stress signs like workers staying outside the nest or refusing food.

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