Lasius aphidicola

Lasius aphidicola - "Shaded Fuzzy Ant"

Lasius aphidicola is a small to medium-sized ant native to North America, recognized by its yellow to pale brown coloration and distinctive short, bristly hairs on the gaster. Workers measure approximately 3-5mm, while queens are larger at 7-9mm. The species was only recently distinguished from the European Lasius umbratus in 2018,so older North American records often refer to it under that name ^[1]. These ants inhabit moist soils in open woodlands, forest edges, and farm fields across Canada, the United States, and Mexico, typically nesting under stones or in rotting logs and stumps ^[2].

Quick Summary

• Difficulty: Expert
• Origin & Habitat: North America (Canada, United States, Mexico), moist soil in open woodlands, early successional forests, forest edges, and farm fields ^[2]
• Colony Type: Temporary social parasite, queens invade and take over established colonies of host Lasius species (L. americanus, L. niger, L. neoniger)
  • Queen: Socially parasitic, Temporary parasitic
• Size & Growth:
  • Queen: 7-9mm (estimated based on genus typical size)
  • Worker: 3-5mm (estimated based on genus typical size)
  • Colony: Unknown, depends on host colony
  • Growth: Unknown
  • Development: Unknown, depends on host colony development (Development is tied to host colony since this is a temporary social parasite)
• Antkeeping:
  • Temperature: Keep at room temperature (20-24°C), typical for North American Lasius species. A slight gradient is beneficial.
  • Humidity: Requires moist substrate conditions, these ants naturally nest in damp soil. Keep the nest substrate consistently moist but not waterlogged.
  • Diapause: Yes, likely requires winter hibernation like other North American Lasius species. Provide a cool period around 5-10°C for 3-4 months.
  • Nesting: Naturalistic setups with moist soil work well. These ants nest under stones and in rotting wood in the wild, so a soil-based formicarium or test tube setup with damp substrate is appropriate.
• Behavior: This species is a temporary social parasite, queens must invade established colonies of host Lasius species to found new colonies. Workers are not aggressive and spend most of their time underground tending aphids for honeydew. They are rarely seen above ground except on cloudy days. Escape risk is moderate, standard barrier methods work well.
• Common Issues: difficulty establishing colonies, requires obtaining a host colony first, queen adoption failure, host colonies often reject invading queens, slow colony growth, dependent on host worker cooperation, specific host requirements, may only accept certain Lasius species as hosts, parasitic nature makes this species unsuitable for beginners

Understanding the Parasitic Lifestyle

Lasius aphidicola is a temporary social parasite, which means its queens cannot found colonies the way most ants do. Instead, a newly mated queen must find an established colony of another Lasius species (typically Lasius americanus, Lasius niger, or Lasius neoniger) and infiltrate it. The queen kills the host queen and uses the host workers to raise her first brood. Once her own workers emerge, they gradually replace the host workers until the colony becomes purely L. aphidicola. This parasitic relationship is why this species is considered expert-level, you cannot simply set up a queen in a test tube and wait for workers to appear. You must first establish a host colony, then introduce the parasite queen. ^[1][2]

Housing and Nest Setup

Because this is a parasitic species, you need two colonies to keep it successfully: a host colony and the parasite colony. For the host, any common North American Lasius species like L. americanus or L. niger works well. The nest should mimic their natural conditions, moist soil substrate in a naturalistic setup or test tube with a water reservoir. L. aphidicola itself will eventually occupy part of the same setup once the parasite queen establishes herself. Use standard escape prevention (Fluon on edges) since workers are small but not tiny. ^[2]

Feeding and Diet

In the wild, Lasius aphidicola workers feed primarily on the honeydew excreted by aphids and coccids. These ants are often found in close association with these sap-sucking insects, sometimes tending them in underground galleries. Workers may venture above ground on cloudy days to forage. In captivity, offer sugar water or honey water as a substitute for honeydew. Protein should be provided occasionally in the form of small insects, though this species is not a heavy predator. The host colony will also need standard Lasius diet. ^[2]

Temperature and Seasonal Care

Keep both host and parasite colonies at typical room temperature (20-24°C). These ants are native to temperate North America and do not require heated setups. During winter, provide a hibernation period of 3-4 months at cool temperatures (5-10°C), mimicking natural seasonal cycles. This is essential for colony health and reproduction. Place the setup in a cool basement or refrigerator during winter dormancy. ^[2]

Introducing the Parasite Queen

Introducing a L. aphidicola queen to a host colony is challenging and often fails. Host workers typically attack and kill the intruding queen. Some keepers report success by introducing the queen when the host colony is queenless, or by using colony fragments. Wilson (1955) documented multiple failed attempts to introduce L. aphidicola queens into host colonies of L. pallitarsis, L. americanus, and L. neoniger. The key is finding the right host species and timing. L. neoniger may not be a natural host, so focus on L. americanus or L. niger. ^[2]

Frequently Asked Questions

References