Lasius brevicornis

Lasius brevicornis - "Short-horned Meadow Ant"

Lasius brevicornis is a small yellow to pale brown ant native to eastern North America. Workers measure around 3-5mm, while queens are larger at 6-8mm. This species has notably tiny eyes with fewer than 35 ommatidia, and can be identified by the last segment of its maxillary palp being shorter than or equal to the penultimate segment ^[1]. The species was historically confused with the European Lasius flavus until genetic analysis confirmed it as a distinct species in 2018 ^[2]. Colonies are typically single-queen (monogyne) and nest underground under rocks in open habitats and dry woodlands ^[1]. This ant is a generalist predator that also tends root aphids and feeds on their honeydew ^[1].

Quick Summary

• Difficulty: Easy
• Origin & Habitat: Eastern North America, ranging from Nova Scotia and Quebec south to Florida, west to Alberta, Washington, and California ^[3]. Found in open habitats and dry woodlands, nesting under stones ^[1].
• Colony Type: Single-queen (monogyne) colonies. This is typical for Lasius species in the flavus group.
  • Colony: Monogyne
  • Founding: Claustral
• Size & Growth:
  • Queen: 6-8mm (estimated based on flavus group species)
  • Worker: 3-5mm ^[1]
  • Colony: Unknown for this specific species, but flavus group colonies typically reach several thousand workers
  • Growth: Moderate
  • Development: 6-10 weeks (estimated based on typical Lasius development) (Development time is inferred from related Lasius species, actual timing may vary based on temperature conditions)
• Antkeeping:
  • Temperature: Keep at room temperature, around 20-24°C. A slight gradient is beneficial but not required.
  • Humidity: Moderate humidity is suitable. These subterranean ants prefer somewhat dry conditions compared to forest-dwelling species.
  • Diapause: Yes, as a temperate species, colonies require a winter rest period of 3-4 months at around 5-10°C
  • Nesting: Test tube setups work well for founding colonies. Established colonies can be kept in Y-tong nests or naturalistic setups with soil. They prefer compact nesting chambers close to a food water source.
• Behavior: Workers are small and pale, typically foraging underground or in hidden locations. They are not aggressive and rarely venture into open areas, which makes them less visible than many ant species. The colony is generally peaceful and not prone to biting or stinging. Escape risk is moderate, their small size means they can slip through small gaps, so standard barrier precautions are recommended.
• Common Issues: colonies often appear inactive during founding because queens seal themselves in and workers stay hidden underground, small colony size makes them less impressive than larger species during early growth stages, they prefer dark, concealed spaces and may avoid nests with excessive light, wild-caught colonies may have parasites that can devastate captive colonies, their subterranean lifestyle means they may not be visible for long periods

Housing and Nest Setup

Lasius brevicornis adapts well to standard antkeeping setups. For founding colonies, a test tube setup with a water reservoir works perfectly, the queen seals herself in a chamber and the workers expand from there. Use a test tube with at least 10cm of water reservoir capacity, connected to a small outworld for foraging. Once the colony reaches 50+ workers, you can transition to a Y-tong (acrylic) nest or a naturalistic setup with soil. These ants prefer tight, enclosed spaces and will readily accept carved chambers. Avoid setups with large open areas as they prefer to stay hidden. A small outworld with a sugar water station and protein food dish is sufficient. ^[1]

Feeding and Diet

In the wild, Lasius brevicornis is a generalist predator that also tends root aphids and feeds on their honeydew ^[1]. In captivity, offer sugar water or honey water as a constant energy source. For protein, provide small insects like fruit flies, pinhead crickets, or mealworms. Since they tend underground aphids in nature, they may also acceptaphid honeydew if offered. Feed protein 1-2 times per week, and keep sugar water available at all times. Remove uneaten prey after 24 hours to prevent mold.

Temperature and Seasonal Care

Keep your colony at room temperature, ideally between 20-24°C. This species tolerates the typical temperature range found in most homes. As a temperate North American species, Lasius brevicornis requires a winter dormancy period. Reduce temperatures to 5-10°C for 3-4 months during winter, typically from late autumn through early spring. During this period, reduce feeding significantly, the colony will be mostly inactive. Do not feed during hibernation. Return to normal temperatures gradually in spring to trigger renewed activity and growth. ^[1]

Behavior and Observation

This is a subterranean species, meaning workers spend most of their time hidden in the nest or traveling through underground tunnels. They are not active foragers in the open like some ant species, which can make them seem inactive. Workers are pale yellow to light brown and quite small. They are not aggressive and do not possess a painful sting, their defense is primarily avoidance behavior. Because they are small and secretive, observation can be challenging, but watching the queen tend brood in the nest chambers is rewarding. The colony will establish and grow steadily once the first workers (nanitics) emerge. ^[1]

Frequently Asked Questions

References