Lordomyrma azumai

Lordomyrma azumai

Lordomyrma azumai is a small, reddish-brown myrmicine ant native to Japan, found across Honshu, Shikoku, and Kyushu. Workers measure 4.2-4.7mm with a distinctive appearance featuring deep antennal scrobes, erect body hairs, and a medium reddish-brown coloration with the gaster typically darker than the rest of the body ^[1]. This species is considered the most structurally conservative Asian Lordomyrma, essentially representing the ancestral form of the genus ^[1][2]. They inhabit moist soil horizons in broadleaf forests, nesting under stones, in cracks, or within damp twigs and fallen nuts ^[1].

Quick Summary

• Difficulty: Medium
• Origin & Habitat: Japan (Honshu, Shikoku, Kyushu), with recent range extension to Akita Prefecture in the Tohoku region. Inhabits moist soil horizons with fresh to well-decomposed organic content under natural broadleaf forest at elevations around 350m ^[1][3].
• Colony Type: Monogyne, single-queen colonies. Four colonies examined were all monogynous with worker counts up to 86 individuals ^[1].
  • Colony: Monogyne
• Size & Growth:
  • Queen: 4.9mm ^[1]
  • Worker: 4.2-4.7mm ^[1]
  • Colony: Up to 86 workers, typically 20-30 ^[1][4]
  • Growth: Moderate, inferred from limited colony data showing small worker complements
  • Development: Unknown, direct development data not available. Based on typical Myrmicinae patterns and seasonal timing (alate gynes present mid-February, dealate gyne found alone in late March), estimate 8-12 weeks at optimal temperature ^[1]. (Alate gynes and males present in mid-February colonies, dealate gyne collected alone in leaf-litter in late March suggests nuptial flights occur in early spring ^[1].)
• Antkeeping:
  • Temperature: Keep at 18-22°C. This is a cool-climate Japanese species from moist forest floor habitats, avoid overheating ^[4].
  • Humidity: High humidity required. Nest in consistently moist substrate, these ants naturally inhabit damp soil horizons and will quickly retreat if conditions dry out ^[1][4].
  • Diapause: Likely yes, as a temperate Japanese species, expect a winter rest period around 10-15°C for several months during winter months, matching their natural cycle where alates appear in February ^[1].
  • Nesting: Prefers tight, humid nest chambers. Test tubes with water reservoirs work well, or small acrylic/plaster nests with consistent moisture. They nest under stones and in small cavities in nature, avoid large open spaces ^[1].
• Behavior: Extremely timid and reclusive. Workers quickly retreat to nest chambers at the slightest vibration. When threatened, they perform a remarkable defense behavior: rolling their body into a ball and tucking their antennae completely into their deep antennal scrobes, essentially feigning death ^[4][1]. This species is not aggressive and poses no sting threat to humans. Escape risk is moderate, workers are around 4-5mm so standard barriers are sufficient.
• Common Issues: high humidity maintenance is critical, they will not tolerate dry conditions, timid behavior means they may not thrive in high-traffic areas or with frequent disturbance, colonies remain small (under 100 workers) which may disappoint keepers expecting rapid growth, slow development means beginners may lose patience and abandon the colony, escape prevention should still be practiced despite moderate size, they are active foragers

Housing and Nest Preferences

Lordomyrma azumai requires humid, enclosed nest spaces that mimic their natural microhabitat under stones and within small cavities. Test tube setups with cotton-stoppered water reservoirs work well, the ants will naturally cluster in the humid portion near the water. Alternatively, small acrylic or plaster nests with moisture chambers maintain the damp conditions they need. Avoid large, open formicarium spaces, these ants prefer tight chambers scaled to their small size. Place the nest in a quiet area with minimal vibration, as they are extremely sensitive to disturbances and will retreat quickly when threatened ^[1][4].

Feeding and Diet

This species accepts honey water readily, field observations show workers lick honey water solutions ^[4]. They likely supplement with small insects and other protein sources in captivity. Offer a constant supply of sugar water or honey diluted with water, along with small live prey such as fruit flies, pinhead crickets, or other tiny arthropods. Feed protein 2-3 times per week, removing uneaten prey after 24 hours. The small colony sizes (typically under 100 workers) mean portion sizes should remain modest, overfeeding leads to mold problems in humid setups.

Temperature and Seasonal Care

Keep Lordomyrma azumai cool compared to many tropical ant species. Room temperature in the 18-22°C range is ideal, this matches their native habitat in Japanese broadleaf forests. As a temperate species, they likely require a winter rest period. Reduce temperatures to around 10-15°C during winter months (roughly November through February in the Northern Hemisphere) to allow the colony to enter dormancy. This aligns with their natural cycle where alate gynes and males appear in mid-February, suggesting spring reproduction follows winter rest ^[1]. Avoid heating pads or placing the nest in direct sunlight, overheating and drying are the primary risks.

Behavior and Temperament

The most notable aspect of Lordomyrma azumai behavior is their extreme timidity. When workers foraging outside the brood chamber detect any vibration, even faint vibrations from someone walking nearby, they immediately retreat into the nest chamber ^[4]. When physically disturbed, they perform an unusual defensive display: workers fold their antennae completely into deep grooves (antennal scrobes) on the sides of their head, roll their body into a tight ball, and remain motionless, essentially feigning death ^[1][4]. This is a non-aggressive species with no sting threat to keepers. They are not escape artists, but standard barrier methods should still be used. Their small colony size and shy nature make them best suited for keepers who enjoy observing quiet, unobtrusive ant behavior.

Colony Development and Growth

Colonies remain relatively small throughout their life cycle, with maximum worker counts around 86 individuals observed in the wild ^[1]. Typical colonies number 20-30 workers ^[4]. This is not a species that will produce hundreds of workers quickly. The development timeline is not directly documented, but based on the appearance of alate gynes and males in mid-February and dealate (wingless) queens found alone in late March, nuptial flights appear to occur in early spring ^[1]. Expect slow, steady growth with a colony taking perhaps 1-2 years to reach 50 workers under optimal conditions. The small colony size makes them suitable for long-term observation but less satisfying for keepers seeking rapid colony expansion.

Frequently Asked Questions

References