Dolichoderus varians

Dolichoderus varians

Dolichoderus varians is a small to medium-sized ant species native to the northern South American tropics. Workers measure around 3-4mm with a dark brown to black coloration and the characteristic Dolichoderus trait of a slit-like anal opening (they lack the acidopore that fire ants and many other ants have). The species has a well-developed basidorsal tubercle on the hind coxa, short erect hairs on the mesosoma, and a rugose propodeum without distinct carinae or angles ^[1]. This ant inhabits tropical rainforest environments across the Amazon basin, with documented records from Brazil, Colombia, Ecuador, and French Guiana ^[2]. It is not commonly encountered and appears to prefer primary forest habitats.

Quick Summary

• Difficulty: Medium
• Origin & Habitat: Tropical rainforest of the Amazon basin in Brazil, Colombia, Ecuador, and French Guiana ^[2]. Found in primary forest environments including logged and burnt forest areas in Pará, Brazil ^[3].
• Colony Type: Likely monogyne (single queen colonies) based on typical Dolichoderus patterns. Colony size is unknown but likely moderate, similar species in the genus typically reach a few hundred workers.
  • Colony: Monogyne
  • Founding: Claustral
• Size & Growth:
  • Queen: Estimated 5-7mm based on genus patterns
  • Worker: Approximately 3-4mm ^[1]
  • Colony: Unknown, estimated a few hundred workers based on genus patterns
  • Growth: Moderate, estimated based on related Dolichoderus species
  • Development: Estimated 6-10 weeks at tropical temperatures (24-28°C) (Development time is inferred from related Dolichoderus species, specific data for D. varians is not available)
• Antkeeping:
  • Temperature: Keep at 24-28°C. These are tropical ants requiring warm, stable temperatures. A heating cable on one side of the nest creates a suitable gradient.
  • Humidity: High humidity (70-80%) mimicking tropical rainforest conditions. Keep the nest substrate consistently moist but not waterlogged.
  • Diapause: No, being a tropical species, they do not require hibernation. Maintain warm temperatures year-round.
  • Nesting: In nature they likely nest in rotting wood, under bark, or in arboreal cavities in the rainforest. In captivity, a Y-tong (AAC) nest or naturalistic setup with wood pieces works well. They prefer tight, humid chambers.
• Behavior: Dolichoderus ants are generally not aggressive and are considered peaceful colony residents. They forage for honeydew and small insects. Workers are active and can move quickly. Their small size (3-4mm) means escape prevention should be moderate, they are not tiny enough to require fine mesh barriers like some genera, but standard formicarium precautions apply. They lack a functional stinger but can still defend by biting and using chemical secretions.
• Common Issues: tropical species may decline if temperatures drop below 22°C, keep consistently warm, wild-caught colonies may be stressed from collection and transport, leading to colony failure, limited natural history data means care is based on genus inference rather than species-specific research, high humidity requirements can lead to mold issues if ventilation is inadequate

Housing and Nest Setup

Dolichoderus varians does best in a Y-tong (AAC) nest or a naturalistic setup with rotting wood pieces. They prefer tight, humid chambers that mimic their natural arboreal nesting sites in tropical forests. A test tube setup can work for founding colonies, but transfer to a proper nest is recommended once the colony reaches 15-20 workers. The nest material should retain moisture well, plaster or acrylic nests with water reservoirs work better than dry setups. Provide a small outworld for foraging with a sugar water station and protein prey. ^[1][2]

Feeding and Diet

Like other Dolichoderus species, D. varians likely feeds primarily on honeydew collected from aphids and scale insects, plus small insects for protein. In captivity, offer a constant source of sugar water or honey, and provide small protein sources like fruit flies, small mealworms, or cricket pieces twice weekly. They are not aggressive predators but will scavenge small insects. Avoid large prey items that they cannot subdue. Fresh fruit can also be accepted occasionally.

Temperature and Humidity

These tropical ants require warm temperatures between 24-28°C. A heating cable placed on one side of the nest creates a thermal gradient they can regulate by moving between chambers. Temperature drops below 22°C can stress colonies and slow or stop brood development. Humidity should be high (70-80%), the nest substrate should feel consistently moist. Mist the outworld occasionally but avoid letting water pool in the nest area. Good ventilation is essential to prevent mold while maintaining humidity. ^[3]

Colony Establishment

Established colonies may be difficult to find since this species is not common. If you obtain a founding queen, she is likely claustral, she will seal herself in a chamber and raise the first workers (nanitics) entirely on her stored fat reserves. Do not disturb the founding chamber for at least 4-6 weeks. Once the first workers emerge, they will begin foraging. The colony will grow slowly at first, then accelerate as the worker force increases. Expect 6-10 weeks from egg to first worker at optimal temperatures.

Behavior and Temperament

Dolichoderus varians is a peaceful species that rarely shows aggression. Workers are active foragers, primarily collecting honeydew but also scavenging small insects. They do not have a functional stinger but can bite and secrete defensive chemicals from their anal gland. The colony will likely establish multiple chambers for brood storage and food caching. Workers communicate using chemical trails to guide nestmates to food sources. They are not escape artists, standard barrier methods are sufficient for this species. ^[4][5]

Ecological Notes

In the wild, Dolichoderus varians has been documented as prey of the army ant Eciton hamatum in Ecuador ^[4][5]. This indicates they are part of the forest floor and lower canopy fauna that army ants prey upon. They are not commonly encountered, the species is described as 'not very common' in Colombia ^[1]. Their distribution spans the Amazon basin, with records from primary forest habitats in Brazil, Colombia, Ecuador, and French Guiana.

Frequently Asked Questions

References