Myrmica surusumi

Quick Summary

• Difficulty: Medium
• Origin & Habitat: Japan Alps (central Honshu) at 1,400-2,000m elevation, and Hokkaido at lower elevations (up to 900m). Nests in soil in open, dry areas and grassland ^[1].
• Colony Type: Colony structure is unconfirmed for this newly described species. Based on typical Myrmica genus patterns, most species in this genus are single-queen colonies.
• Size & Growth:
  • Queen: 5.3-5.7mm (total length) ^[1]
  • Worker: 4.1-4.3mm (total length) ^[1]
  • Colony: Unknown, no colony size data available for this newly described species
  • Growth: Unknown, estimated as moderate based on related Myrmica species
  • Development: Estimated 6-10 weeks at optimal temperature based on related Myrmica species (Development timeline is unconfirmed for this species. Related Myrmica species typically take 6-10 weeks from egg to worker at room temperature.)
• Antkeeping:
  • Temperature: Keep at 18-22°C as a starting range. As a highland Japanese species, it likely prefers cooler conditions. Provide a temperature gradient so ants can self-regulate. Avoid overheating.
  • Humidity: Nests in dry, open soil in nature. Keep nest substrate moderately moist but allow some drying between waterings. Do not keep overly wet.
  • Diapause: Yes, as a highland Japanese species from cold elevations, a winter dormancy period is essential. Keep at 5-10°C for 3-4 months during winter (roughly November-February in the Northern Hemisphere).
  • Nesting: Soil-nesting species. In captivity, a test tube setup works well for founding colonies. For established colonies, a Y-tong or plaster nest with moderate humidity is suitable. Provide a dry outworld area for foraging.
• Behavior: Typical Myrmica behavior, workers are active foragers and moderately aggressive when defending the nest. They possess a stinger. Workers are medium-sized so escape prevention should be moderate. They likely accept a standard Myrmica diet of sugar sources and protein prey.
• Common Issues: this is a newly described species with limited captive husbandry data, some trial and error may be needed, hibernation is critical for this cold-adapted species, skipping winter dormancy likely harms colony health, highland origin means they prefer cooler conditions, overheating can be fatal, dry grassland nesting preference means they do better with drier nest conditions than many ants, colony size data is unknown, growth expectations are based on related species rather than direct observation

Housing and Nest Setup

Myrmica surusumi nests in soil in open, dry areas in nature ^[1]. For captivity, start founding colonies in a standard test tube setup with a water reservoir and cotton plug. Once the colony reaches 20-30 workers, you can transition to a more permanent nest. A Y-tong or plaster nest works well, these allow you to control humidity while providing a dry foraging area. Since they come from dry grassland habitats, keep the nest substrate moderately moist but not wet. Provide a separate outworld for foraging with a shallow water dish and protein food offerings. Escape prevention should be moderate, workers at 4.2mm are not tiny but can still escape through small gaps if motivated.

Feeding and Diet

Like other Myrmica species, M. surusumi likely accepts a standard ant diet. Offer sugar water, honey, or diluted maple syrup as a constant carbohydrate source. For protein, offer small insects like fruit flies, small crickets, mealworms, or other appropriately sized prey. In nature, Myrmica workers forage for honeydew from aphids and small invertebrates. Feed protein 2-3 times per week, and ensure a sugar source is always available. Remove uneaten prey after 24-48 hours to prevent mold. Since this is a newly described species with no specific dietary studies, monitor whether your colony accepts different food types and adjust accordingly.

Temperature and Seasonal Care

This is a highland Japanese species adapted to cool conditions ^[1]. Keep the nest area at 18-22°C as a starting point, they will likely do better on the cooler end of this range. Avoid temperatures above 25°C, as overheating can be fatal. Provide a temperature gradient so workers can choose their preferred zone. During winter (roughly November through February in the Northern Hemisphere), the colony must undergo a hibernation period. Move the colony to a cool location around 5-10°C, a refrigerator set to this range or an unheated garage works well. Ensure the nest substrate remains slightly moist during hibernation but not wet. This winter dormancy is essential for the health of the colony, as the species is adapted to cold mountain environments.

Colony Development and Growth

As a species described in 2024,there is no captive husbandry data for M. surusumi. Queens measure 5.3-5.7mm and workers are 4.1-4.3mm in total length ^[1]. Based on typical Myrmica development, expect the first workers (nanitics) to emerge 6-10 weeks after the queen lays eggs, assuming temperatures around 20°C. Initial colony growth is slow, the queen raises the first brood alone. Once workers emerge, growth accelerates but remains moderate compared to faster-growing genera. The founding process means the queen seals herself in a chamber and does not leave to forage during the founding stage, she relies on stored fat reserves. Do not disturb a founding colony unnecessarily during this period.

Behavior and Temperament

Myrmica workers are known for their alert, active foraging behavior and moderate aggression when defending the nest. Workers likely communicate through chemical signals and will defend aggressively if the nest is threatened. Like other Myrmica, they possess a stinger, though the sting may be mild due to the small size of the ants. Workers are medium-sized at 4.2mm, making them capable of basic escape prevention but not as challenging as tiny species. They will likely show typical Myrmica behaviors including active foraging, brood care, and colony defense. Observe your colony's activity patterns, active foraging during the day and tending to brood indicates a healthy, established colony.

Frequently Asked Questions

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References