Large blue butterfly is a 4-star creature card from the Steam Age. Large blue caterpillars trick red ants into carrying them home, then eat the ants' brood.
Bonus by grade
| Grade | Copies needed | Bonus |
|---|---|---|
| Common | 0 | +12% population growth |
| Uncommon | 2 | +21.6% population growth |
| Rare | 5 | +36% population growth |
| Epic | 10 | +54% population growth |
| Legendary | 20 | +84% population growth |
Duplicates raise the grade: Uncommon at 2, Rare at 5, Epic at 10, Legendary at 20.
Codex
- Common: The large blue (Phengaris arion) is a butterfly.
- Uncommon: Its caterpillars smell like ant larvae.
- Rare: Myrmica ants carry them into their nest.
- Epic: The caterpillars eat the ants' brood for months.
- Legendary: It died out in Britain in 1979 and was brought back.
Field notes are reviewed regularly. Spot something wrong? Tell us.
Field guide
| Size | Not well known |
| Nest | Warm, grazed grassland with wild thyme and Myrmica red ants |
| Diet | Caterpillars eat thyme flowers, then ant grubs; adults sip nectar |
| Defence | Caterpillars smell like ant larvae, so ants adopt rather than attack them |
| Active | Adults fly in June and July, usually on sunny days |
| Lifespan | Adults live about 5 days on average, up to about 2 weeks |
| Where it lives | Most of Europe, plus Turkey, Russia, Mongolia, China and Japan |
Did you know?
- The caterpillar drops to the ground at about 4 mm, then is carried into a Myrmica nest.
- It spends roughly ten months underground, then pupates in the nest in spring.
- One caterpillar can eat up to about 1,200 ant grubs.
Sources: butterfly-conservation.org, learnbutterflies.com