Oxyepoecus mandibularis

Quick Summary

• Difficulty: Expert
• Origin & Habitat: Known only from a single collection in Songo, Bolivia ^[1], in the Neotropical region ^[2]. The exact habitat is unrecorded.
• Colony Type: Unknown, only a single worker has ever been documented. No queens, males, or colony structure has been observed.
• Size & Growth:
  • Queen: Unknown, queens have never been documented for this species
  • Worker: 3 mm total length ^[1]
  • Colony: Unknown, no colonies have ever been observed
  • Growth: Unknown
  • Development: Unknown, no breeding colonies have ever been documented (This species is known from a single worker specimen collected in 1913. No captive colonies exist.)
• Antkeeping:
  • Temperature: Unknown, no specific data exists. Based on genus Oxyepoecus patterns ^[2], start around 24-26°C and observe colony activity.
  • Humidity: Unknown, no specific data exists. Based on genus patterns ^[2], keep nest substrate consistently moist but not waterlogged.
  • Diapause: Unknown, no seasonal data exists. As a Neotropical species, it may not require formal hibernation.
  • Nesting: Unknown, no natural nesting observations exist. Based on genus patterns ^[2], likely nests in small chambers in soil, under stones, or in rotting wood.
• Behavior: Behavior is completely unobserved. The genus Oxyepoecus contains small, generally non-aggressive ants that typically forage individually or in small groups ^[2]. Workers are around 3 mm, so escape prevention should be moderate, they are small but not among the tiniest ants. As members of the Solenopsidini tribe, they likely possess a stinger, but no data on sting potency exists.
• Common Issues: no captive colonies exist, this species has never been kept in captivity and may not be available to hobbyists ^[1]., complete lack of biological data means all care recommendations are speculative guesses based on genus patterns ^[2]., extremely rare, only known from a single specimen collected over 100 years ago ^[1]., no queen or colony structure data means founding behavior cannot be predicted., risk of keeping a species that may have specialized ecological requirements we cannot determine.

A Note on This Extremely Rare Species

Oxyepoecus mandibularis represents one of the most poorly documented ant species in the world. It was originally described by Carlo Emery in 1913 based on a single worker specimen collected in Songo, Bolivia ^[1]. Since then, no additional specimens have been found, no colonies have ever been observed, and no biological information exists in the scientific literature ^[1][2]. The holotype specimen is likely housed in the Emery collection in Genoa, Italy, but has not been examined in recent revisions ^[1]. This means there is essentially no captive husbandry information available, every recommendation for this species must be inferred from what we know about related ants in the genus Oxyepoecus and the broader Solenopsidini tribe ^[2]. If you somehow obtain this species, you would essentially be pioneering its captive care with no prior guidance. This makes it an expert-level species in the truest sense.

Taxonomy and Identification

This species was originally described as Monomorium (Martia) mandibulare by Emery in 1913 before being transferred to the genus Oxyepoecus by Ettershank in 1966 ^[1]. The species name 'mandibularis' refers to its distinctive large mandibles ^[1]. The worker is relatively large for the genus at 3 mm total length ^[1]. Key identification features include the long mandibles with four large teeth (the basal tooth is thickened and clearly separated from the others), very long antennal scapes that nearly reach the occipital border, and distinctive sculpture patterns on the head, promesonotum, and propodeum ^[1]. In identification keys, it runs close to Oxyepoecus rastratus but can be distinguished by its longer median tooth, shorter lateral tooth, and different sculpture patterns ^[1].

Genus-Level Information

The genus Oxyepoecus contains approximately 15 described species distributed throughout the Neotropical region, primarily in South America ^[2]. They are small to tiny Myrmicinae ants that typically form small colonies ^[2]. Some species in the genus have been suggested to have socially parasitic relationships with other ants, though this varies by species ^[2]. Workers are generally modest in size, with some species being among the smallest ants known ^[2]. The genus is part of the Solenopsidini tribe, which includes fire ants (Solenopsis) and other small Myrmicinae ^[2]. Based on related genera, Oxyepoecus species likely feed on small invertebrates, honeydew, and nectar ^[2]. However, specific dietary preferences for O. mandibularis are completely unknown.

Housing and Care Recommendations

Since no specific data exists for O. mandibularis, housing recommendations must be based on what works for similar tiny Neotropical Myrmicinae ^[2]. Use test tubes for founding colonies, a small chamber with a water reservoir at one end works well ^[2]. The tube should be kept humid but not flooded. For established colonies, small Y-tong style nests or 3D-printed nests with appropriately scaled chambers work well ^[2]. Because workers are around 3 mm, use tight-fitting barriers and fine mesh to prevent escapes ^[1]. Temperature should be in the warm range (24-26°C) with a slight gradient if possible ^[2]. Humidity should be moderate to high ^[2]. Feed small protein sources like fruit flies, pinhead crickets, or similar small prey, along with sugar water or honey ^[2]. However, since this species has never been kept in captivity, all of these recommendations are speculative and should be adjusted based on observed colony behavior.

The Challenge of Documenting New Species Information

If you are fortunate enough to locate or maintain this species, documenting its biology would represent a significant contribution to myrmecology. Keep detailed notes on founding behavior, colony development, worker behavior, temperature and humidity preferences, and dietary acceptance. Photograph queens, workers, and all brood stages if possible. This species represents a genuine opportunity to document biological information that has been unknown for over a century. Consider collaborating with professional myrmecologists to ensure your observations are properly recorded in the scientific literature. The antkeeping community would greatly benefit from any confirmed information about this mysterious species.

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