Cataulacus simoni

Cataulacus simoni

Cataulacus simoni is a small arboreal ant measuring 3.8-4.1mm for workers and around 5mm for queens. They belong to the granulatus species group and are distinguished by their relatively narrow head, large eyes, and the presence of short clavate (club-shaped) hairs on their body. The workers have a black body with reddish appendages and a densely punctured, opaque appearance ^[1]. This species is restricted to Sri Lanka and the Andaman Islands in the Indian Ocean^[2].

Nothing is known about the specific biology of Cataulacus simoni, including their founding behavior, colony structure, or exact nesting preferences ^[2]. However, as a member of the genus Cataulacus, they are likely arboreal nesters, similar to other species in this genus which typically nest in rotting wood, hollow twigs, and tree cavities in tropical forests.

Quick Summary

• Difficulty: Unknown
• Origin & Habitat: Sri Lanka and Andaman Islands, found in lowland wet forest reserves ^[3][4]. They appear to be restricted to these tropical regions in South Asia.
• Colony Type: Unconfirmed, colony structure has not been documented for this species ^[2].
• Size & Growth:
  • Queen: 5.0mm
  • Worker: 3.8-4.1mm
  • Colony: Unknown, no colony size data available
  • Growth: Unknown
  • Development: Unknown, no development data exists for this species (Based on typical Myrmicinae patterns, expect 6-10 weeks at warm tropical temperatures, but this is a rough estimate only)
• Antkeeping:
  • Temperature: Likely 24-28°C based on their tropical Sri Lanka/Andaman distribution, provide a warm, stable temperature gradient and adjust based on colony activity
  • Humidity: Likely requires moderate to high humidity (60-80%) given their wet forest habitat in Sri Lanka, keep nest substrate moist but not waterlogged
  • Diapause: Unknown, tropical species may not require formal hibernation but may show reduced activity during cooler periods
  • Nesting: Likely arboreal, provide rotting wood setups, cork bark, or Y-tong nests with wood-based substrate. They probably prefer nesting in wood cavities like other Cataulacus species ^[2].
• Behavior: Behavior is undocumented for this species ^[2]. Based on genus-level knowledge, Cataulacus ants are typically arboreal, somewhat slow-moving, and not particularly aggressive. Their small size (under 4mm) means escape prevention is important, use fine mesh barriers and tight-fitting lids. They likely forage in trees and surrounding vegetation rather than on the ground.
• Common Issues: no biological data exists, keepers must extrapolate from genus patterns, tropical humidity needs may be difficult to maintain consistently, small size makes escape prevention critical, completely unconfirmed diet preferences, must experiment with common ant foods, no documented founding behavior, unknown if claustral or semi-claustral

Species Overview and Identification

Cataulacus simoni is a small arboreal ant species described by Emery in 1893,originally collected from Sri Lanka (Kandy and Colombo). Workers measure 3.8-4.1mm in total length, making them one of the smaller Cataulacus species. They can be identified by their relatively narrow head with large eyes, the presence of distinctly clavate (club-shaped) hairs on the head and alitrunk, and fine sculpturing on the body surface. The head and thorax have a reticulate-rugose pattern with finely punctured interspaces, giving a dull shine. Propodeal spines are variable, ranging from distinct short structures to small teeth. The species was previously known as Cataulacus simoni before being synonymized with C. simoni. ^[1][2]

Distribution and Habitat

Cataulacus simoni appears to be restricted to Sri Lanka and the Andaman Islands in the Indian Ocean^[2]. In Sri Lanka, they have been recorded in lowland wet forest reserves ^[3][4]. The species has also been reported from mainland India including Meghalaya in the northeast and Kerala in the south, as well as from the Andaman and Nicobar Islands ^[5]. There are also old records from China, though these may require verification. Their presence in wet forest habitats suggests they prefer humid, shaded tropical environments with access to trees and decaying wood for nesting.

Nesting and Housing

Nesting behavior has not been documented for Cataulacus simoni specifically ^[2]. However, the genus Cataulacus is known to be arboreal, with species typically nesting in rotting wood, hollow twigs, tree cavities, and similar elevated microhabitats. For captive care, provide a naturalistic setup with rotting wood, cork bark, or a Y-tong/plaster nest with wood-based substrate. The nest should maintain moderate to high humidity (60-80%) to simulate their wet forest habitat. Ensure adequate ventilation to prevent mold while maintaining humidity. Because they are small (under 4mm), use appropriately scaled chambers and fine mesh barriers for escape prevention.

Feeding and Diet

The specific diet of Cataulacus simoni is completely undocumented ^[2]. Based on typical Cataulacus behavior and related Myrmicinae ants, they likely forage for honeydew, small insects, and may accept sugar sources. Start with standard ant foods: sugar water or honey as an energy source, and protein sources like small mealworms, fruit flies, or other tiny insects. Monitor for acceptance and adjust feeding based on colony preferences. Because nothing is known about their specific dietary needs, be prepared to experiment with various food types. Avoid overfeeding as uneaten food can mold in the humid setup they require.

Temperature and Environmental Needs

As a tropical species from Sri Lanka and the Andaman Islands, Cataulacus simoni likely requires warm temperatures in the range of 24-28°C. Their presence in lowland wet forests suggests they prefer stable, warm, and humid conditions. Provide a temperature gradient so the ants can self-regulate, a heating cable on one side of the nest can create this gradient. Monitor colony activity to determine if temperature adjustments are needed. If workers cluster near the heat source, increase temperature slightly, if they avoid heated areas, reduce heat. Since nothing is known about their diapause requirements, assume they do not require formal hibernation, but may show reduced activity during cooler periods. ^[2]

Known Information Gaps

It cannot be overstated that virtually nothing is known about the biology of Cataulacus simoni ^[2]. No research exists on their colony founding behavior, queen number (monogyne vs polygyne), development timeline, specific habitat preferences, or behavior in captivity. This makes them a challenging species to keep for beginners, as there are no established care protocols to follow. Keepers must be prepared to experiment and document their observations carefully. The genus-level information provided here (arboreal nesting, likely tropical temperature needs) represents the best available guidance, but species-specific requirements may differ significantly. Consider starting with more commonly kept species if you are new to antkeeping.

Frequently Asked Questions

References