Lasius bombycinus

Lasius bombycinus

Lasius bombycinus is a small to medium-sized ant belonging to the Lasius alienus species group, recently described in 2016. Workers measure around 3-4mm with a distinctive dense, whitish pubescence that gives their body a silky appearance. They are medium to dark brown with lighter reddish-yellow mandibles, antennae, and sometimes tibiae. This species has a Balkan-Anatolian distribution, found from eastern Austria through the Balkans to Turkey, where they inhabit warm, dry grasslands and rocky areas. They nest under stones or in hidden soil nests, sometimes building small soil mounds covered in herbs. Queens are notably larger than related species like Lasius alienus and Lasius psammophilus.

Quick Summary

• Difficulty: Easy
• Origin & Habitat: Warm, dry grasslands and rocky areas across the Balkans and Anatolia, from sea level to 2350m elevation. Found in xerothermous grassland, urban gardens in Turkey, and mountain forests in Greece ^[1][2].
• Colony Type: Monogyne, single queen colonies. Confirmed monogynous from Crete studies ^[3]. All Lasius species show independent colony foundation (claustral founding) ^[4].
  • Colony: Monogyne
  • Founding: Claustral
• Size & Growth:
  • Queen: Larger than L. alienus and L. psammophilus, estimated 6-8mm based on related species
  • Worker: 3-4mm (HL 0.777-1.037mm, HW 0.712-0.982mm) ^[5]
  • Colony: Unknown for this species specifically, but related Lasius alienus group species typically reach several thousand workers
  • Growth: Moderate, workers develop until July after spring oviposition ^[1]
  • Development: Estimated 6-10 weeks based on typical Lasius development patterns (Oviposition starts in spring, workers emerge by July. Timeline inferred from related species as direct measurements not available for this species.)
• Antkeeping:
  • Temperature: Keep at 20-24°C. This is a warmth-loving species from Mediterranean climates, but avoid overheating. Room temperature is often suitable.
  • Humidity: Low to moderate. They prefer dry to moderately damp conditions, think warm grassland, not rainforest. Allow the nest to dry out between waterings.
  • Diapause: Yes, likely requires winter rest period. Related Lasius species typically hibernate at 5-10°C for 2-3 months. Given their Balkan-Anatolian range, expect a diapause requirement.
  • Nesting: Test tubes or Y-tong nests work well. They naturally nest under stones and in soil. Provide a small chamber setup with some substrate for nesting. Avoid overly humid conditions.
• Behavior: Generally peaceful and not aggressive. Workers forage on soil surface, in herb layer, and on bushes, they are active foragers. They tend aphids for honeydew and are predatory on small invertebrates. They have moderate escape risk due to their small size, use standard barriers. Workers are not known for stinging.
• Common Issues: colonies may fail if kept too humid, they prefer dry conditions, small size means escape prevention matters, use fine mesh barriers, slow founding phase may cause beginners to overcheck the queen, wild-caught colonies may have parasites, quarantine and observe new colonies

Housing and Nest Setup

Lasius bombycinus does well in standard ant keeping setups. Test tubes work perfectly for founding colonies, use a water reservoir tube attached to a foraging area. For established colonies, Y-tong (acrylic) nests or plaster nests work well. These ants naturally nest under stones and in soil, so provide some substrate options. They prefer drier conditions than many ants, avoid overly humid setups. A small outworld with simple sugar and protein offerings completes the setup. Because they are small (3-4mm), ensure your setup has no gaps that allow escapes. ^[1][3]

Feeding and Diet

In the wild, Lasius bombycinus is zoophagous, they hunt small invertebrates like springtails, small beetles, and other tiny arthropods ^[1]. They also tend aphids for honeydew (trophobiosis) and have been observed tending Lycaenidae butterfly caterpillars ^[1]. In captivity, offer sugar water or honey as a constant energy source. For protein, provide small live prey like fruit flies, pinhead crickets, or mealworms. They will also accept dead insects. Feed protein 2-3 times per week and keep sugar water available at all times. Remove uneaten prey after 24 hours to prevent mold.

Temperature and Seasonal Care

This is a warmth-loving species from Mediterranean climates. Keep temperatures in the 20-24°C range, room temperature is often suitable. They can tolerate temperatures up to around 28°C but avoid prolonged heat exposure. As a species from the Balkans and Turkey, they require a winter diapause. Reduce temperatures to 5-10°C for 2-3 months during winter (roughly November-February in the Northern Hemisphere). Place the colony in a cool location like an unheated garage or refrigerator during this period. Do not feed during diapause but keep the water tube filled. ^[1][5]

Colony Founding

Lasius bombycinus queens practice claustral founding, after mating, the queen seals herself in a small chamber and raises her first workers entirely on stored body fat, without foraging. She lays eggs in spring after overwintering, and workers emerge by July ^[1]. A laboratory observation documented a founding queen raising 26 workers without any feeding ^[1]. This means you should leave a newly mated queen completely alone in her test tube setup for the first few weeks. Do not disturb her while she is sealed in her chamber. Once workers emerge, you can begin offering sugar water and tiny prey.

Behavior and Foraging

Workers are active foragers, searching for food on the soil surface, in the herb layer, and even on bushes ^[1]. They are not particularly aggressive and rarely sting. Their small size makes them quick movers, and they will readily explore their outworld for food. They form moderate-sized colonies that grow steadily over several years. Workers communicate through chemical trails and will recruit nestmates to good food sources. They are generally peaceful toward each other within the colony.

Growth and Development

Colony growth is moderate. After founding, expect the first batch of workers (nanitics) to emerge by mid-summer if the queen mated the previous fall. Growth continues through the first year, typically reaching 50-100 workers by winter. Subsequent years see steady growth to several hundred workers, then eventually thousands in mature colonies. The colony will produce alates (reproductive males and females) in late summer, typically August-October, matching their natural swarming period ^[1].

Frequently Asked Questions

References