Crematogaster kelleri

Crematogaster kelleri

Crematogaster kelleri is a small to medium-sized ant native to Madagascar and the Seychelles. Workers measure 0.6-1.2mm and come in two distinct color forms: a variable brown form (ranging from pale tan to nearly black) and a bright yellow form that stays consistent within colonies. This species is arboreal by nature, building nests in dead branches, under bark, and in moss mats on tree trunks, though they occasionally nest on the ground under stones or in rotting logs. Colonies can be polydomous, meaning they spread across multiple nest sites on a single tree. What makes this species particularly interesting is its remarkable morphological variation, even within the same colony, you'll find workers of different sizes and colors working together ^[1].

Quick Summary

• Difficulty: Medium
• Origin & Habitat: Madagascar and Seychelles, found throughout humid and dry forests from sea level to 2000m elevation, with highest numbers in lowland rainforests and littoral forests ^[1][2]
• Colony Type: Likely monogyne (single queen) with polydomous nest structure, colonies spread across multiple nest sites in trees ^[1]
  • Colony: Monogyne
  • Founding: Claustral
• Size & Growth:
  • Queen: 1.15-1.42mm ^[2], estimated from morphology
  • Worker: 0.60-1.16mm ^[1]
  • Colony: Likely moderate, large colonies documented but exact numbers unknown ^[3]
  • Growth: Moderate, estimated based on tropical arboreal ant patterns
  • Development: 6-8 weeks, estimated from related Crematogaster species (Development time is estimated based on typical tropical Myrmicinae patterns. Direct measurements for this species are not available.)
• Antkeeping:
  • Temperature: Keep at 24-28°C, these are tropical forest ants that prefer warmth. A gentle gradient allows workers to regulate their temperature
  • Humidity: Moderate to high, arboreal species need humidity but not saturation. Provide a moist nest area with some dry areas available. Mist occasionally but avoid standing water
  • Diapause: No true diapause, as a tropical species from Madagascar, they do not require hibernation. Activity may slow slightly during cooler months but no special winter treatment is needed
  • Nesting: Arboreal nesters need vertical space and climbing opportunities. Y-tong (AAC) nests work well, or provide dead branches/twigs in a naturalistic setup. They prefer tight chambers and narrow passages scaled to their small size ^[1][2]
• Behavior: These ants are active foragers that patrol trees and vegetation. They are not particularly aggressive but will defend their nest vigorously. Workers are excellent climbers and will explore vertical surfaces readily. Their small size means escape prevention must be excellent, they can squeeze through tiny gaps. Colonies can grow quite large and may become territorially dominant in their enclosure ^[3].
• Common Issues: escape prevention is critical due to their tiny size, use fine mesh and tight-fitting lids, polydomous colonies may spread workers throughout the outworld, ensure all areas are secure, wild-caught colonies may have parasites that affect survival in captivity, overheating is a risk, keep away from direct sunlight and excessive heat sources, colonies may abandon nest sites if conditions are unsuitable, monitor for stress behaviors

Nest Preferences and Housing

Crematogaster kelleri is an arboreal species that naturally nests in dead branches, under bark, and in canopy moss. In captivity, they do well in Y-tong (acrylic) nests with chambers sized appropriately for their small workers. Provide vertical space and include twigs or branches for them to explore, this mimics their natural arboreal habitat. The nest should have tight-fitting connections to the outworld since these tiny ants can escape through remarkably small gaps. A naturalistic setup with actual twigs or small branches works well if you can maintain proper humidity. Keep the nest area humid but ensure adequate ventilation to prevent mold. ^[1][2]

Feeding and Diet

Like most Crematogaster species, these ants are omnivorous and will accept a variety of foods. Offer sugar sources regularly, honey water or sugar water is readily accepted. They also need protein from insect sources such as small crickets, fruit flies, or mealworms. In the wild, they forage for honeydew from aphids and scale insects, so they may also accept sugary liquids. Feed them every 2-3 days, removing any uneaten prey after 24 hours. A constant sugar source is recommended since they have high energy demands from their active foraging.

Temperature and Seasonal Care

As a tropical species from Madagascar, Crematogaster kelleri prefers warm conditions around 24-28°C. They are found from sea level to 2000m elevation in various forest types, indicating they can tolerate a range of conditions but prefer warmth and humidity. No hibernation or diapause is required, these ants remain active year-round. Avoid temperature extremes and keep them away from direct sunlight which can overheat the nest quickly. A heating cable on one side of the nest can create a temperature gradient if your room temperature falls below 24°C. Monitor colony activity, if workers cluster near the heat source, increase temperature slightly. ^[1]

Behavior and Colony Structure

This species exhibits polydomous nesting behavior in the wild, meaning colonies occupy multiple nest sites across a single tree. In captivity, this may translate to workers exploring and potentially establishing secondary nest sites in different areas of their enclosure. Colonies can grow quite large and become dominant within their territory. Workers are active foragers that readily climb vertical surfaces. They are not particularly aggressive toward keepers but will defend their nest vigorously if threatened. The two color forms (brown and yellow) can appear in the same population, and colonies may contain workers of different sizes, this variation is completely normal for this species. ^[1][3]

Growth and Development

Queen size ranges from 1.15-1.42mm, making them relatively small among Crematogaster. Workers show significant size variation within colonies, ranging from 0.6-1.2mm. Development from egg to worker likely takes 6-8 weeks at optimal temperatures based on related species patterns. The first workers (nanitics) will be smaller than mature workers and may be lighter in color. Growth rate is moderate, expect several months before you have a substantial worker population. Colonies continue growing as long as conditions are suitable and the queen remains healthy. ^[1]

Escape Prevention

Due to their very small size (workers under 1.2mm), excellent escape prevention is essential. Use test tube setups with cotton plugs that are properly fitted, or better yet, use dedicated ant keeping equipment with tight-sealing lids. Any connections between nest and outworld should have multiple barriers. Fine mesh (at least 0.5mm or smaller) is necessary for any ventilation openings. Check all seams and edges regularly, these tiny ants can find gaps you might miss. A barrier of fluon or petroleum jelly on the upper rim of the outworld provides an additional deterrent.

Frequently Asked Questions

References