Monomorium boltoni

Quick Summary

• Difficulty: Expert
• Origin & Habitat: Endemic to Monte Gordo, the highest mountain of São Nicolau Island, Cape Verde. Found only near the mountain's peak in a small pocket of habitat where it survives among rocky terrain at high elevation ^[1].
• Colony Type: Single-queen colonies with ergatoid (wingless) replacement reproductives only, this species lacks typical winged queens ^[2].
• Size & Growth:
  • Queen: size data unavailable, ergatoid queens are wingless and develop from workers, making them smaller than typical winged queens
  • Worker: approximately 2-3mm, inferred from Monomorium genus typical size
  • Colony: size data unavailable, likely small given restricted habitat
  • Growth: Unknown
  • Development: estimated 4-8 weeks based on typical Monomorium development (Development timeline has not been directly studied. Estimates based on related Monomorium species.)
• Antkeeping:
  • Temperature: Keep warm, being from a tropical island, they prefer consistently warm conditions. Temperature requirements are unconfirmed, start around 24-26°C and observe colony behavior.
  • Humidity: Provide a humidity gradient, keep part of the nest moist and part dry. Cape Verde has a semi-arid climate but Monte Gordo's peak likely has slightly more moisture.
  • Diapause: Unknown, being from a tropical island near the equator, they likely do not require true hibernation but may have reduced activity during cooler periods.
  • Nesting: In nature they likely nest in small cavities under stones or in rocky soil at high elevation. In captivity, a small test tube setup or Y-tong nest with tight, appropriately scaled chambers works well.
• Behavior: This species is poorly documented in captivity. Based on genus behavior, they are likely relatively docile and not aggressive. Workers are tiny and may be shy. Escape prevention is critical due to their very small size, use fine mesh barriers and ensure all openings are sealed. They likely forage for small prey and honeydew. This species has a sting but is too small to penetrate human skin effectively.
• Common Issues: this species is extremely rare in the wild and critically endangered, it is not available to hobbyists, escape prevention is critical due to their tiny size, virtually no captive breeding information exists, this is not a species for beginners, wild populations are threatened by invasive ants and habitat loss, ergatoid reproduction means no nuptial flights, colonies reproduce differently than typical ants

Distribution and Conservation Status

Monomorium boltoni is one of the most restricted ant species in the world, known only from a tiny area near the summit of Monte Gordo on São Nicolau Island in Cape Verde ^[1]. This mountain is the highest point on the island, and the ant survives in just one small pocket of habitat, found within 100 meters of the peak ^[1]. The species faces severe existential threat from the invasive big-headed ant (Pheidole megacephala), which has been spreading up the mountain and could overrun the ant's last refuge ^[1]. This makes M. boltoni a conservation priority, and it is highly unlikely to be available for the antkeeping hobby given its critically endangered status in the wild.

Unique Reproductive Biology

This species is remarkable for having only ergatoid queens, wingless queens that develop from worker larvae rather than typical winged queens that disperse during nuptial flights ^[2]. This is unusual in the ant world and means the colonies reproduce differently than most ant species. Instead of new queens dispersing to found colonies elsewhere, ergatoid queens typically remain in or near the parent nest and may become replacement reproductives if the primary queen dies. This reproductive system is sometimes called 'queen dimorphism' in the genus Monomorium, though M. boltoni appears to have only the ergatoid form ^[2]. For antkeepers, this means you would not observe nuptial flights, colony reproduction happens through the emergence of ergatoid reproductives within established colonies.

Housing and Nest Setup

Given their tiny size, housing must be appropriately scaled with very small chambers and narrow passages. A small test tube setup works well for founding colonies, while established colonies can be moved to a Y-tong nest with appropriately sized chambers. Escape prevention is absolutely critical, these tiny ants can squeeze through the smallest gaps. Use fine mesh on any ventilation holes, ensure all lids fit tightly, and consider using Fluon or another barrier coating on the outer edges of the outworld. Provide a small water tube and offer food on a shallow dish to minimize drowning risk.

Feeding

Like other Monomorium species, M. boltoni is likely omnivorous, accepting small protein sources and sugar. Offer small live prey appropriate to their size, such as fruit flies, pinhead crickets, or tiny insects. They will likely accept sugar water, honey, or diluted honey as an energy source. Feed small amounts a few times per week, removing any uneaten prey after 24 hours to prevent mold.

Temperature and Seasonal Care

Being from tropical Cape Verde, this species prefers consistently warm temperatures. Temperature requirements are unconfirmed, start around 24-26°C and observe colony behavior. A heating cable placed on one side of the nest can create a temperature gradient, allowing the ants to regulate their own exposure to warmth. Monitor colony behavior, if workers cluster near the heat source, the nest may be too cool, if they avoid the heated area, it may be too warm. Since they come from an island location near the equator, they likely do not require a true hibernation period, though activity may slow during cooler months.

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