Polyrhachis queenslandica

Polyrhachis queenslandica

Polyrhachis queenslandica is a medium-sized arboreal ant native to northern Queensland, Australia and New Guinea. Workers measure 5.95-6.70mm with queens reaching 8.11-9.17mm ^[1]. They are mostly black or very dark reddish-brown in color, distinguishing them from the similar P. delicata which has reddish markings ^[1]. These ants are weaver ants, they use silk produced by their larvae to bind together leaves of rainforest trees and shrubs, creating protective nests suspended in the canopy ^[2][1]. Unlike many ground-nesting ants, they are entirely arboreal and rarely descend to the forest floor.

Quick Summary

• Difficulty: Medium
• Origin & Habitat: Northern Queensland, Australia and New Guinea. Found in lowland rainforest trees and shrubs where they build silk-woven nests among leaves ^[1][2].
• Colony Type: Multi-queen colonies with multiple arboreal nests per colony ^[2][3]. Queens are chunky at 8-9mm with substantial fat reserves for claustral founding ^[1].
  • Colony: Polygyne
  • Founding: Claustral
• Size & Growth:
  • Queen: 8.11-9.17mm ^[1]
  • Worker: 5.95-6.70mm ^[1]
  • Colony: Unknown, likely moderate colonies of several hundred workers based on typical Polyrhachis patterns
  • Growth: Moderate, likely slower than ground-nesting species due to arboreal lifestyle
  • Development: Estimated 8-12 weeks based on typical tropical Polyrhachis development (Pupae are in cocoons, requiring slightly longer development than naked pupae ^[2])
• Antkeeping:
  • Temperature: Keep at 24-28°C, they are a tropical species from Queensland rainforest ^[1]. A gentle gradient allowing thermoregulation is ideal.
  • Humidity: High humidity (70-85%), rainforest species that needs moisture. Mist regularly and provide water in the outworld.
  • Diapause: No, being tropical, they do not require hibernation. Keep warm year-round.
  • Nesting: Arboreal specialists, they need vertical space and climbing opportunities. Provide a formicarium with multiple chambers connected vertically, or a naturalistic setup with branches and live plants where they can build silk nests. Y-tong or acrylic nests work well with added vertical climbing structures.
• Behavior: Generally calm and non-aggressive compared to many Formicinae. Workers are active foragers that search for honeydew and small insects in the canopy. They are excellent climbers and will readily traverse branches and plant material. Escape risk is moderate, they are not tiny but are agile climbers. Use barrier tape or fluon on smooth surfaces.
• Common Issues: high humidity maintenance, rainforest species prone to mold in poorly ventilated setups, arboreal nature means they need vertical space, horizontal-only nests lead to stress, silk-weaving behavior requires humidity to work, too dry prevents nest construction, tropical species cannot tolerate cool temperatures, keep above 24°C, wild-caught colonies may be stressed from canopy collection and need time to acclimate

Nest Preferences and Housing

Polyrhachis queenslandica is an arboreal species that naturally nests in the canopy of rainforest trees, using silk to bind leaves together into protective chambers ^[2][1]. In captivity, they need vertical space and climbing opportunities to express their natural behaviors. A Y-tong (AAC) or acrylic formicarium works well, but you should add branches, cork bark, or artificial plants to provide climbing structures. Some keepers successfully keep them in naturalistic setups with live tropical plants where the ants can build their silk nests among the leaves. The key is vertical space, they will not thrive in flat, horizontal-only nests. Provide multiple connected chambers at different heights to mimic their multi-nest colony structure ^[2].

Feeding and Diet

Like most Polyrhachis species, P. queenslandica is omnivorous with a diet based on honeydew from sap-sucking insects and small invertebrates. In captivity, offer a varied diet including sugar water or honey as a constant energy source. For protein, provide small insects like fruit flies, small crickets, or mealworms. They are active foragers and will readily take prey back to the nest. Feed protein 2-3 times per week and keep sugar water available at all times. Fresh water should always be accessible. Being a tropical species, they have moderate metabolic demands, avoid overfeeding which can lead to mold issues in their humid setup. ^[2]

Temperature and Seasonal Care

As a tropical species from Queensland and New Guinea, P. queenslandica requires warm temperatures year-round. Keep the nest area at 24-28°C with a slight gradient if possible so workers can thermoregulate. A heating cable on one side of the nest can help maintain warmth, but avoid direct heat that could dry out the nest. They do not require hibernation or diapause, keeping them warm year-round is essential for colony health. Cool temperatures below 22°C can slow activity and may stress the colony. Room temperature in most homes is acceptable if kept in the warmer range. ^[1]

Humidity and Water

P. queenslandica comes from Queensland rainforest habitats and requires high humidity to thrive ^[1]. Maintain 70-85% humidity in the nest area by misting regularly and using a water reservoir in your formicarium. The humidity also supports their silk-weaving behavior, too dry and they cannot properly construct their characteristic leaf nests. However, balance humidity with adequate ventilation to prevent mold growth. Provide a water tube or cotton ball with fresh water in the outworld at all times. Monitor condensation levels in the nest, some condensation is normal and desirable for this species.

Behavior and Colony Structure

This species forms polygynous colonies, multiple queens coexist in colonies that span several arboreal nests ^[2][3]. Workers are medium-sized, dark-colored, and relatively calm compared to many aggressive ant species. They are excellent climbers and spend most of their time in the canopy layer. In captivity, they will explore vertical structures and appreciate opportunities to forage at different heights. The presence of multiple queens means colonies can grow quite large, but growth rate is moderate. Pupae are enclosed in cocoons, which is typical for the subgenus Myrmothrinax and adds to their development time compared to species with naked pupae ^[2].

Frequently Asked Questions

References