Mesostruma turneri

Mesostruma turneri

Mesostruma turneri is a tiny, rare Australian ant measuring just 3-4mm in total length. Workers have a distinctive almost-square head with large, protruding eyes and a honey-yellow body with slightly darker coloration on the head. This species belongs to the tribe Attini and is closely related to the trap-jaw ants (Strumigenys group). It was collected only once in 1894 near Mackay, Queensland, making it one of the rarest and least-studied Australian ants. It represents the northernmost extent of the genus Mesostruma. ^[1][2]

Quick Summary

• Difficulty: Unknown, likely Expert
• Origin & Habitat: Northern Queensland, Australia. The single known collection was from dry, low woodland along the coastal strip near Mackay, Queensland. ^[2][1]
• Colony Type: Unknown, colony structure has never been documented. Based on related genera in the Attini tribe, likely single-queen colonies.
• Size & Growth:
  • Queen: Unknown, queen has not been described ^[2]
  • Worker: 3.0-4.0mm total length, with head width 0.72-0.89mm ^[2][1]
  • Colony: Unknown, no colony data exists
  • Growth: Unknown, no development data exists
  • Development: Unknown, no direct measurements exist. Based on related small Myrmicinae, estimate 6-10 weeks at optimal temperature. (Estimated from related genus patterns, no species-specific data available)
• Antkeeping:
  • Temperature: Unconfirmed, no thermal studies exist. Based on Queensland coastal habitat, likely tolerates 22-28°C. Start around 24°C and observe colony activity.
  • Humidity: Unconfirmed, no humidity data. Dry woodland habitat suggests moderate humidity needs, roughly 50-70%. Keep nest substrate slightly moist but allow some drying.
  • Diapause: Unknown, no overwintering data exists for this species. Queensland experiences mild winters, so a true diapause may not be required.
  • Nesting: No captive nesting data exists. In nature, likely nests in soil or under stones in dry woodland. A small test tube setup or Y-tong nest with narrow chambers would suit their tiny size.
• Behavior: Behavior is unstudied. Based on related genera (Strumigenys, Epopostruma), these ants are likely predatory on small invertebrates and may use their trap-jaw mandibles to capture prey. Their large, protruding eyes suggest visual hunting may play a role. Escape prevention is critical due to their tiny 3-4mm size, they can easily slip through standard barrier setups.
• Common Issues: extremely rare in the wild, virtually no captive colonies exist, no established care protocols, all advice is speculative based on related species, tiny size means escape prevention must be excellent, no documented diet preferences, must experiment with small live prey, no information on founding behavior or colony development

Rarity and Collection History

Mesostruma turneri is one of the rarest ants in the world, known from a single collection made in May 1894 by Gilbert Turner near Mackay, Queensland. The original collection site has since been converted to agricultural land. This species represents the northernmost extent of the genus Mesostruma, which otherwise extends southward into New South Wales and Victoria. No additional specimens have been documented since the original collection, making any information about this species extremely limited. ^[2][1]

Identification and Morphology

Workers measure 3.0-4.0mm in total length with an almost square head (cephalic index 96-103). The most distinctive features include very broad, convex heads with large, strongly protruding eyes. The body has dense, shallow foveolate punctures, and the first gastral segment has evenly spaced elongate rugae. Body coloration is honey yellow with the dorsum of the head slightly darker. The propodeal lamellae are broad with weakly convex dorsal margins. These tiny ants can be distinguished from similar species like Mesostruma inornata by the distinctive rugae pattern on the first gastral segment. ^[2][1]

Taxonomy and Relationships

Mesostruma turneri was originally described as Strumigenys (Epopostruma) turneri by Forel in 1895,then transferred to Epopostruma by Emery in 1924,and finally to Mesostruma by Brown in 1948. This species belongs to the tribe Attini within the subfamily Myrmicinae. While the Attini are famous for fungus-growing, the genus Mesostruma is not a fungus-grower, it belongs to the broader dacetine ant group that includes the famous trap-jaw ants (Strumigenys). These ants share the characteristic large eyes and specialized mandibles with their trap-jaw relatives. ^[2][1]

Housing and Care Recommendations

Since no captive breeding records exist for this species, all care recommendations are speculative based on related genera. Use a small test tube setup or Y-tong nest with chambers scaled to their tiny 3-4mm size. Escape prevention must be excellent, these ants will easily pass through standard barriers. For substrate, use slightly moist but not wet material. Temperature around 24°C is a reasonable starting point based on their Queensland habitat. Feeding will require experimentation, likely accepts small live prey such as springtails, fruit flies, or other micro-arthropods. Sugar water acceptance is uncertain. Due to the complete lack of captive husbandry information, this species is not recommended for beginners and should only be kept by experienced antkeepers willing to document their findings.

Research Gaps

This species represents a complete mystery in antkeeping. No information exists on: colony size, queen characteristics, founding behavior, development timeline, diet preferences, temperature/humidity requirements, nuptial flight timing, or any aspect of captive care. The entire global population in captivity appears to be zero or near-zero. Any successful captive husbandry would represent a significant scientific contribution. Keepers interested in this species should be prepared to document their observations carefully and potentially publish their findings.

Frequently Asked Questions

References