Mayriella occidua

Mayriella occidua

Mayriella occidua is an extremely rare tiny myrmicine ant described from Western Australia. Workers are among the smallest ants you'll encounter, measuring just 0.44mm in head width ^[1]. This species is known from only a single specimen collected in the Nuyts Wilderness area near Walpole, making it one of the most poorly documented ants in Australia. The genus Mayriella is distinguished by its elongated eyes, deep antennal scrobes, and ten-segmented antennal club ^[2]. The few known specimens were collected in December 2003 during a survey in a pine area ^[1]. This is the only Mayriella species found in Western Australia, extending the genus range westward by nearly 2,000km from its previously known eastern Australian distribution ^[1].

Quick Summary

• Difficulty: Expert
• Origin & Habitat: South-western Australia, specifically the Nuyts Wilderness area near Walpole in Western Australia (approx. 35°04'S 116°38'E). The only known specimen was collected in a pine area during a December survey ^[1].
• Colony Type: Unknown, only worker caste has been described. Colony structure has not been documented.
• Size & Growth:
  • Queen: Unknown, queen has not been described
  • Worker: 0.44mm head width, approximately 2-3mm total length ^[1]
  • Colony: Unknown, only single worker known
  • Growth: Unknown
  • Development: Unknown (No development data exists for this species. Related Mayriella species suggest development may take several months, but this is entirely speculative.)
• Antkeeping:
  • Temperature: Unknown for this species. Based on its south-western Australian distribution (Mediterranean climate), room temperature (18-24°C) is likely appropriate. Monitor colony activity and adjust as needed.
  • Humidity: Unknown. The Walpole region is relatively moist. Keep nest substrate moderately humid with some drier areas available.
  • Diapause: Unknown, likely experiences seasonal slowdown given the temperate climate of south-western Australia, but specific requirements are unconfirmed.
  • Nesting: Unknown natural nesting preferences. The single specimen was collected in a pine area, suggesting forested habitats. Use a small test tube setup or Y-tong nest with appropriately scaled chambers for their tiny size.
• Behavior: Behavior is undocumented. Given the genus Mayriella typically contains cryptic, slow-moving ants that nest in small cavities, expect them to be shy and non-aggressive. Their tiny size makes escape prevention critical, they can squeeze through standard test tube barriers. Handle with extreme care as they are fragile.
• Common Issues: only one specimen has ever been found, this species is exceptionally rare and may have specialized requirements, queen and colony structure completely unknown, you cannot establish a colony without a queen, tiny size makes them extremely difficult to house and feed, escape prevention is critical due to their minute size, virtually no captive breeding data exists, this is not a species for beginners

Species Overview and Rarity

Mayriella occidua is an extraordinarily rare ant species known from a single worker specimen collected in 2003. This makes it one of the least-studied ants in Australia, with virtually no biological information available beyond the original species description. The genus Mayriella contains only eight species worldwide, with M. occidua being the only species recorded from Western Australia ^[1]. The discovery extended the known range of this genus westward by nearly 2,000km, as previous species were only found along the eastern coast of Australia ^[1]. This species should be considered a collector's curiosity rather than a practical species for antkeeping, as no captive colonies have ever been established.

Identification and Morphology

Workers are tiny, measuring approximately 0.44mm in head width and 0.50mm in head length ^[1]. The species can be identified by its cylindrical or slightly barrel-shaped postpetiole that lacks lateral expansions when viewed from above. The petiole has distinct dorsal and posterior faces separated by an obtuse angle, which differentiates it from the similar M. abstinens found in Queensland and NSW ^[1]. Sculpturing consists of large, closely spaced pits on the dorsal surface of the mesosoma. Propodeal spines are short and triangular. The dorsum of the postpetiole and gaster lacks erect hairs, except for a row along the posterior margin of the gastral tergite ^[1]. The genus is distinguished from other Myrmicinae by its elongated eyes, deep antennal scrobes, and ten-segmented antennal club ^[2].

Distribution and Habitat

This species is known only from the Nuyts Wilderness in the Walpole-Nornalup National Park in south-western Western Australia (approximately 35°04'S 116°38'E) ^[1]. The region has a Mediterranean climate with cool, wet winters and warm, dry summers. The single known specimen was collected in December 2003 (southern hemisphere summer) in an area with pines ^[1]. The Walpole region is known for its tall karri and tingle forests and receives moderate annual rainfall. This represents the westernmost record for the genus Mayriella in Australia, with other species found along the eastern coast from Queensland to Tasmania ^[2].

Keeping Considerations

This species is NOT recommended for antkeeping. No queen has ever been described, no colony has been successfully maintained in captivity, and virtually nothing is known about their biology, diet, or reproductive behavior. The only known specimen is a single worker in a museum collection. If you somehow obtain a Mayriella occidua queen (which would be a significant scientific discovery), you would essentially be pioneering captive husbandry for this species. For those interested in Mayriella, the more commonly kept species in the genus Mayriella abstinens from eastern Australia would be a more practical choice, though even that species remains rarely kept in captivity.

Related Species

Mayriella occidua is most similar to Mayriella abstinens, which is found along the Queensland and New South Wales coasts ^[1]. The genus Mayriella contains eight species worldwide, with six known from Australia. M. ebbei occurs in the Adelaide region and is geographically closest to M. occidua, but M. occidua is morphologically more similar to M. abstinens despite the greater geographic distance ^[1]. Other Australian species include M. transfuga and M. spinosior, though distribution details vary. The genus is considered rare throughout its range, with most species known from only a handful of specimens.

Frequently Asked Questions

References