Polyrhachis tonsilis

Quick Summary

• Difficulty: Medium
• Origin & Habitat: North Sumatra, Indonesia, specifically the Sibolangit area in a tropical rainforest region ^[1][2].
• Colony Type: Colony structure is unconfirmed, no specific data on queen number or social structure.
• Size & Growth:
  • Queen: Size data unavailable, no total length measurements for queens in literature.
  • Worker: 9.7-10.0 mm ^[1].
  • Colony: Unconfirmed, estimated up to a few thousand workers based on genus patterns.
  • Growth: Moderate, inferred from typical Polyrhachis development.
  • Development: Estimated 6-10 weeks at tropical temperatures, based on genus patterns ^[2]. (Direct development data unavailable, estimates rely on typical Polyrhachis genus patterns.)
• Antkeeping:
  • Temperature: Keep warm, around 24-28°C, with a gradient for self-regulation. Inferred from tropical origin ^[2].
  • Humidity: Keep nest substrate consistently moist but not waterlogged. Inferred from tropical habitat ^[2].
  • Diapause: No diapause required, tropical species do not need hibernation ^[2].
  • Nesting: Prefer enclosed spaces like Y-tong (AAC), plaster, or soil nests with wood pieces. Inferred from genus patterns ^[2].
• Behavior: Calm and non-aggressive based on genus patterns. Workers may use spines for defense, and as Formicinae, they spray formic acid instead of stinging. Standard escape prevention is recommended due to moderate size.
• Common Issues: temperature drops below 22°C can slow colony activity and development., wild-caught colonies may carry parasites or diseases that cause failure., slow establishment period for founding colonies may delay worker production., limited availability in the antkeeping hobby due to recent species status.

Species Background and Identification

Polyrhachis tonsilis was recognized as a distinct species in 2019,previously considered a variety of Polyrhachis bihamata ^[1]. Key features include bicolored appearance, strongly shiny gaster tergites, and paired transverse carinae on the propodeum ^[1]. The hooked spines on the petiole are characteristic of spiny ants in the subgenus Polyrhachis ^[1]. Males and queens are not described, and biology is poorly known ^[1][2].

Housing and Nest Preferences

In captivity, use Y-tong (AAC), plaster, or naturalistic soil nests with wood pieces to mimic natural preferences ^[2]. Ensure the nest is dark and enclosed, with adequate humidity control, substrate should be damp but not saturated. Provide a water tube or cotton ball with water. Avoid excessively large enclosures for founding colonies to reduce stress.

Feeding and Diet

Polyrhachis ants are omnivorous. Offer sugar water, honey, or diluted syrup as a constant energy source. Provide protein 2-3 times per week with small insects like fruit flies or mealworms ^[2]. Remove uneaten prey after 24-48 hours to prevent mold. Fresh water should always be accessible.

Temperature and Seasonal Care

Maintain temperatures between 24-28°C with a gradient using a heating mat on one side ^[2]. Avoid temperatures below 22°C for extended periods, as this can slow activity. No diapause is needed for this tropical species. Keep away from drafts or air conditioning vents.

Behavior and Colony Dynamics

Workers are calm and not aggressive toward keepers. They forage actively and may use spines defensively. As Formicinae, they lack a sting and spray formic acid for defense. Colonies grow moderately, with first workers taking several months. Worker lifespans are moderate, with continuous replacement as the colony grows.

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